commands.txt

cmake-commands(7)
*****************

Normal Commands
===============

These commands may be used freely in CMake projects.

add_compile_options
-------------------

Adds options to the compilation of source files.

::

 add_compile_options(<option> ...)

Adds options to the compiler command line for sources in the current
directory and below.  This command can be used to add any options, but
alternative commands exist to add preprocessor definitions
(``target_compile_definitions()`` and ``add_definitions()``) or
include directories (``target_include_directories()`` and
``include_directories()``).  See documentation of the
``directory`` and
`` target`` ``COMPILE_OPTIONS`` properties.

Arguments to ``add_compile_options`` may use "generator expressions" with
the syntax ``$<...>``.  See the ``cmake-generator-expressions(7)``
manual for available expressions.  See the ``cmake-buildsystem(7)``
manual for more on defining buildsystem properties.

add_custom_command
------------------

Add a custom build rule to the generated build system.

There are two main signatures for add_custom_command The first
signature is for adding a custom command to produce an output.

::

 add_custom_command(OUTPUT output1 [output2 ...]
                    COMMAND command1 [ARGS] [args1...]
                    [COMMAND command2 [ARGS] [args2...] ...]
                    [MAIN_DEPENDENCY depend]
                    [DEPENDS [depends...]]
                    [IMPLICIT_DEPENDS <lang1> depend1
                                     [<lang2> depend2] ...]
                    [WORKING_DIRECTORY dir]
                    [COMMENT comment] [VERBATIM] [APPEND])

This defines a command to generate specified OUTPUT file(s).  A target
created in the same directory (CMakeLists.txt file) that specifies any
output of the custom command as a source file is given a rule to
generate the file using the command at build time.  Do not list the
output in more than one independent target that may build in parallel
or the two instances of the rule may conflict (instead use
add_custom_target to drive the command and make the other targets
depend on that one).  If an output name is a relative path it will be
interpreted relative to the build tree directory corresponding to the
current source directory.  Note that MAIN_DEPENDENCY is completely
optional and is used as a suggestion to visual studio about where to
hang the custom command.  In makefile terms this creates a new target
in the following form:

::

 OUTPUT: MAIN_DEPENDENCY DEPENDS
         COMMAND

If more than one command is specified they will be executed in order.
The optional ARGS argument is for backward compatibility and will be
ignored.

The second signature adds a custom command to a target such as a
library or executable.  This is useful for performing an operation
before or after building the target.  The command becomes part of the
target and will only execute when the target itself is built.  If the
target is already built, the command will not execute.

::

 add_custom_command(TARGET target
                    PRE_BUILD | PRE_LINK | POST_BUILD
                    COMMAND command1 [ARGS] [args1...]
                    [COMMAND command2 [ARGS] [args2...] ...]
                    [WORKING_DIRECTORY dir]
                    [COMMENT comment] [VERBATIM])

This defines a new command that will be associated with building the
specified target.  When the command will happen is determined by which
of the following is specified:

::

 PRE_BUILD - run before all other dependencies
 PRE_LINK - run after other dependencies
 POST_BUILD - run after the target has been built

Note that the PRE_BUILD option is only supported on Visual Studio 7 or
later.  For all other generators PRE_BUILD will be treated as
PRE_LINK.

If WORKING_DIRECTORY is specified the command will be executed in the
directory given.  If it is a relative path it will be interpreted
relative to the build tree directory corresponding to the current
source directory.  If COMMENT is set, the value will be displayed as a
message before the commands are executed at build time.  If APPEND is
specified the COMMAND and DEPENDS option values are appended to the
custom command for the first output specified.  There must have
already been a previous call to this command with the same output.
The COMMENT, WORKING_DIRECTORY, and MAIN_DEPENDENCY options are
currently ignored when APPEND is given, but may be used in the future.

If VERBATIM is given then all arguments to the commands will be
escaped properly for the build tool so that the invoked command
receives each argument unchanged.  Note that one level of escapes is
still used by the CMake language processor before add_custom_command
even sees the arguments.  Use of VERBATIM is recommended as it enables
correct behavior.  When VERBATIM is not given the behavior is platform
specific because there is no protection of tool-specific special
characters.

If the output of the custom command is not actually created as a file
on disk it should be marked as SYMBOLIC with
SET_SOURCE_FILES_PROPERTIES.

The IMPLICIT_DEPENDS option requests scanning of implicit dependencies
of an input file.  The language given specifies the programming
language whose corresponding dependency scanner should be used.
Currently only C and CXX language scanners are supported.  The
language has to be specified for every file in the IMPLICIT_DEPENDS
list.  Dependencies discovered from the scanning are added to those of
the custom command at build time.  Note that the IMPLICIT_DEPENDS
option is currently supported only for Makefile generators and will be
ignored by other generators.

If COMMAND specifies an executable target (created by ADD_EXECUTABLE)
it will automatically be replaced by the location of the executable
created at build time.  Additionally a target-level dependency will be
added so that the executable target will be built before any target
using this custom command.  However this does NOT add a file-level
dependency that would cause the custom command to re-run whenever the
executable is recompiled.

Arguments to COMMAND may use "generator expressions" with the syntax
``$<...>``.  See the ``cmake-generator-expressions(7)`` manual for
available expressions.

Note that tgt is not added as a dependency of the target this
expression is evaluated on.

::

 $<TARGET_POLICY:pol>          = '1' if the policy was NEW when the 'head' target was created, else '0'.  If the policy was not set, the warning message for the policy will be emitted.  This generator expression only works for a subset of policies.
 $<INSTALL_PREFIX>         = Content of the install prefix when the target is exported via INSTALL(EXPORT) and empty otherwise.

Boolean expressions:

::

 $<AND:?[,?]...>           = '1' if all '?' are '1', else '0'
 $<OR:?[,?]...>            = '0' if all '?' are '0', else '1'
 $<NOT:?>                  = '0' if '?' is '1', else '1'

where '?' is always either '0' or '1'.

Expressions with an implicit 'this' target:

::

 $<TARGET_PROPERTY:prop>   = The value of the property prop on the target on which the generator expression is evaluated.

References to target names in generator expressions imply target-level
dependencies, but NOT file-level dependencies.  List target names with
the DEPENDS option to add file dependencies.

The DEPENDS option specifies files on which the command depends.  If
any dependency is an OUTPUT of another custom command in the same
directory (CMakeLists.txt file) CMake automatically brings the other
custom command into the target in which this command is built.  If
DEPENDS is not specified the command will run whenever the OUTPUT is
missing; if the command does not actually create the OUTPUT then the
rule will always run.  If DEPENDS specifies any target (created by an
ADD_* command) a target-level dependency is created to make sure the
target is built before any target using this custom command.
Additionally, if the target is an executable or library a file-level
dependency is created to cause the custom command to re-run whenever
the target is recompiled.

add_custom_target
-----------------

Add a target with no output so it will always be built.

::

 add_custom_target(Name [ALL] [command1 [args1...]]
                   [COMMAND command2 [args2...] ...]
                   [DEPENDS depend depend depend ... ]
                   [WORKING_DIRECTORY dir]
                   [COMMENT comment] [VERBATIM]
                   [SOURCES src1 [src2...]])

Adds a target with the given name that executes the given commands.
The target has no output file and is ALWAYS CONSIDERED OUT OF DATE
even if the commands try to create a file with the name of the target.
Use ADD_CUSTOM_COMMAND to generate a file with dependencies.  By
default nothing depends on the custom target.  Use ADD_DEPENDENCIES to
add dependencies to or from other targets.  If the ALL option is
specified it indicates that this target should be added to the default
build target so that it will be run every time (the command cannot be
called ALL).  The command and arguments are optional and if not
specified an empty target will be created.  If WORKING_DIRECTORY is
set, then the command will be run in that directory.  If it is a
relative path it will be interpreted relative to the build tree
directory corresponding to the current source directory.  If COMMENT
is set, the value will be displayed as a message before the commands
are executed at build time.  Dependencies listed with the DEPENDS
argument may reference files and outputs of custom commands created
with add_custom_command() in the same directory (CMakeLists.txt file).

If VERBATIM is given then all arguments to the commands will be
escaped properly for the build tool so that the invoked command
receives each argument unchanged.  Note that one level of escapes is
still used by the CMake language processor before add_custom_target
even sees the arguments.  Use of VERBATIM is recommended as it enables
correct behavior.  When VERBATIM is not given the behavior is platform
specific because there is no protection of tool-specific special
characters.

The SOURCES option specifies additional source files to be included in
the custom target.  Specified source files will be added to IDE
project files for convenience in editing even if they have not build
rules.

add_definitions
---------------

Adds -D define flags to the compilation of source files.

::

 add_definitions(-DFOO -DBAR ...)

Adds definitions to the compiler command line for sources in the current
directory and below.  This command can be used to add any flags, but
it is intended to add preprocessor definitions.  Flags
beginning in -D or /D that look like preprocessor definitions are
automatically added to the ``COMPILE_DEFINITIONS`` directory
property for the current directory.  Definitions with non-trivial values
may be left in the set of flags instead of being converted for reasons of
backwards compatibility.  See documentation of the
``directory``,
``target``,
``source file`` ``COMPILE_DEFINITIONS``
properties for details on adding preprocessor definitions to specific
scopes and configurations.

See the ``cmake-buildsystem(7)`` manual for more on defining
buildsystem properties.

add_dependencies
----------------

Add a dependency between top-level targets.

::

 add_dependencies(<target> [<target-dependency>]...)

Make a top-level <target> depend on other top-level targets to ensure
that they build before <target> does.  A top-level target is one
created by ADD_EXECUTABLE, ADD_LIBRARY, or ADD_CUSTOM_TARGET.
Dependencies added to an IMPORTED target are followed transitively in
its place since the target itself does not build.

See the DEPENDS option of ADD_CUSTOM_TARGET and ADD_CUSTOM_COMMAND for
adding file-level dependencies in custom rules.  See the
OBJECT_DEPENDS option in SET_SOURCE_FILES_PROPERTIES to add file-level
dependencies to object files.

add_executable
--------------

Add an executable to the project using the specified source files.

::

 add_executable(<name> [WIN32] [MACOSX_BUNDLE]
                [EXCLUDE_FROM_ALL]
                source1 [source2 ...])

Adds an executable target called ``<name>`` to be built from the source
files listed in the command invocation.  The ``<name>`` corresponds to the
logical target name and must be globally unique within a project.  The
actual file name of the executable built is constructed based on
conventions of the native platform (such as ``<name>.exe`` or just
``<name>``.

By default the executable file will be created in the build tree
directory corresponding to the source tree directory in which the
command was invoked.  See documentation of the
``RUNTIME_OUTPUT_DIRECTORY`` target property to change this
location.  See documentation of the ``OUTPUT_NAME`` target property
to change the ``<name>`` part of the final file name.

If ``WIN32`` is given the property ``WIN32_EXECUTABLE`` will be
set on the target created.  See documentation of that target property for
details.

If ``MACOSX_BUNDLE`` is given the corresponding property will be set on
the created target.  See documentation of the ``MACOSX_BUNDLE``
target property for details.

If ``EXCLUDE_FROM_ALL`` is given the corresponding property will be set on
the created target.  See documentation of the ``EXCLUDE_FROM_ALL``
target property for details.

See the ``cmake-buildsystem(7)`` manual for more on defining
buildsystem properties.

--------------------------------------------------------------------------

::

 add_executable(<name> IMPORTED [GLOBAL])

An :ref:`IMPORTED executable target <Imported Targets>` references an
executable file located outside the project.  No rules are generated to
build it, and the ``IMPORTED`` target property is ``True``.  The
target name has scope in the directory in which it is created and below, but
the ``GLOBAL`` option extends visibility.  It may be referenced like any
target built within the project.  ``IMPORTED`` executables are useful
for convenient reference from commands like ``add_custom_command()``.
Details about the imported executable are specified by setting properties
whose names begin in ``IMPORTED_``.  The most important such property is
``IMPORTED_LOCATION`` (and its per-configuration version
``IMPORTED_LOCATION_<CONFIG>``) which specifies the location of
the main executable file on disk.  See documentation of the ``IMPORTED_*``
properties for more information.

--------------------------------------------------------------------------

::

 add_executable(<name> ALIAS <target>)

Creates an :ref:`Alias Target <Alias Targets>`, such that ``<name>`` can
be used to refer to ``<target>`` in subsequent commands.  The ``<name>``
does not appear in the generated buildsystem as a make target.  The
``<target>`` may not be an :ref:`Imported Target <Imported Targets>` or an
``ALIAS``.  ``ALIAS`` targets can be used as targets to read properties
from, executables for custom commands and custom targets.  They can also be
tested for existance with the regular ``if(TARGET)`` subcommand.
The ``<name>`` may not be used to modify properties of ``<target>``, that
is, it may not be used as the operand of ``set_property()``,
``set_target_properties()``, ``target_link_libraries()`` etc.
An ``ALIAS`` target may not be installed or exported.

add_library
-----------

Add a library to the project using the specified source files.

::

 add_library(<name> [STATIC | SHARED | MODULE]
             [EXCLUDE_FROM_ALL]
             source1 [source2 ...])

Adds a library target called ``<name>`` to be built from the source files
listed in the command invocation.  The ``<name>`` corresponds to the
logical target name and must be globally unique within a project.  The
actual file name of the library built is constructed based on
conventions of the native platform (such as ``lib<name>.a`` or
``<name>.lib``).

``STATIC``, ``SHARED``, or ``MODULE`` may be given to specify the type of
library to be created.  ``STATIC`` libraries are archives of object files
for use when linking other targets.  ``SHARED`` libraries are linked
dynamically and loaded at runtime.  ``MODULE`` libraries are plugins that
are not linked into other targets but may be loaded dynamically at runtime
using dlopen-like functionality.  If no type is given explicitly the
type is ``STATIC`` or ``SHARED`` based on whether the current value of the
variable ``BUILD_SHARED_LIBS`` is ``ON``.  For ``SHARED`` and
``MODULE`` libraries the ``POSITION_INDEPENDENT_CODE`` target
property is set to ``ON`` automatically.

By default the library file will be created in the build tree directory
corresponding to the source tree directory in which thecommand was
invoked.  See documentation of the ``ARCHIVE_OUTPUT_DIRECTORY``,
``LIBRARY_OUTPUT_DIRECTORY``, and
``RUNTIME_OUTPUT_DIRECTORY`` target properties to change this
location.  See documentation of the ``OUTPUT_NAME`` target
property to change the ``<name>`` part of the final file name.

If ``EXCLUDE_FROM_ALL`` is given the corresponding property will be set on
the created target.  See documentation of the ``EXCLUDE_FROM_ALL``
target property for details.

See the ``cmake-buildsystem(7)`` manual for more on defining buildsystem
properties.

--------------------------------------------------------------------------

::

 add_library(<name> <SHARED|STATIC|MODULE|UNKNOWN> IMPORTED
             [GLOBAL])

An :ref:`IMPORTED library target <Imported Targets>` references a library
file located outside the project.  No rules are generated to build it, and
the ``IMPORTED`` target property is ``True``.  The target name has
scope in the directory in which it is created and below, but the ``GLOBAL``
option extends visibility.  It may be referenced like any target built
within the project.  ``IMPORTED`` libraries are useful for convenient
reference from commands like ``target_link_libraries()``.  Details
about the imported library are specified by setting properties whose names
begin in ``IMPORTED_`` and ``INTERFACE_``.  The most important such
property is ``IMPORTED_LOCATION`` (and its per-configuration
variant ``IMPORTED_LOCATION_<CONFIG>``) which specifies the
location of the main library file on disk.  See documentation of the
``IMPORTED_*`` and ``INTERFACE_*`` properties for more information.

--------------------------------------------------------------------------

::

 add_library(<name> OBJECT <src>...)

Creates a special "object library" target.  An object library compiles
source files but does not archive or link their object files into a
library.  Instead other targets created by ``add_library()`` or
``add_executable()`` may reference the objects using an expression of the
form ``$<TARGET_OBJECTS:objlib>`` as a source, where ``objlib`` is the
object library name.  For example:

 add_library(... $<TARGET_OBJECTS:objlib> ...)
 add_executable(... $<TARGET_OBJECTS:objlib> ...)

will include objlib's object files in a library and an executable
along with those compiled from their own sources.  Object libraries
may contain only sources (and headers) that compile to object files.
They may contain custom commands generating such sources, but not
``PRE_BUILD``, ``PRE_LINK``, or ``POST_BUILD`` commands.  Object libraries
cannot be imported, exported, installed, or linked.  Some native build
systems may not like targets that have only object files, so consider
adding at least one real source file to any target that references
``$<TARGET_OBJECTS:objlib>``.

--------------------------------------------------------------------------

::

 add_library(<name> ALIAS <target>)

Creates an :ref:`Alias Target <Alias Targets>`, such that ``<name>`` can be
used to refer to ``<target>`` in subsequent commands.  The ``<name>`` does
not appear in the generatedbuildsystem as a make target.  The ``<target>``
may not be an :ref:`Imported Target <Imported Targets>` or an ``ALIAS``.
``ALIAS`` targets can be used as linkable targets and as targets to
read properties from.  They can also be tested for existance with the
regular ``if(TARGET)`` subcommand.  The ``<name>`` may not be used
to modify properties of ``<target>``, that is, it may not be used as the
operand of ``set_property()``, ``set_target_properties()``,
``target_link_libraries()`` etc.  An ``ALIAS`` target may not be
installed or exported.

--------------------------------------------------------------------------

::

 add_library(<name> INTERFACE [IMPORTED [GLOBAL]])

Creates an :ref:`Interface Library <Interface Libraries>`.  An ``INTERFACE``
library target does not directly create build output, though it may
have properties set on it and it may be installed, exported and
imported. Typically the ``INTERFACE_*`` properties are populated on
the interface target using the ``set_property()``,
``target_link_libraries(INTERFACE)``,
``target_include_directories(INTERFACE)``,
``target_compile_options(INTERFACE)``
and ``target_compile_definitions(INTERFACE)`` commands, and then it
is used as an argument to ``target_link_libraries()`` like any other
target.

An ``INTERFACE`` :ref:`Imported Target <Imported Targets>` may also be
created with this signature.  An ``IMPORTED`` library target references a
library defined outside the project.  The target name has scope in the
directory in which it is created and below, but the ``GLOBAL`` option
extends visibility.  It may be referenced like any target built within
the project.  ``IMPORTED`` libraries are useful for convenient reference
from commands like ``target_link_libraries()``.

add_subdirectory
----------------

Add a subdirectory to the build.

::

 add_subdirectory(source_dir [binary_dir]
                  [EXCLUDE_FROM_ALL])

Add a subdirectory to the build.  The source_dir specifies the
directory in which the source CMakeLists.txt and code files are
located.  If it is a relative path it will be evaluated with respect
to the current directory (the typical usage), but it may also be an
absolute path.  The binary_dir specifies the directory in which to
place the output files.  If it is a relative path it will be evaluated
with respect to the current output directory, but it may also be an
absolute path.  If binary_dir is not specified, the value of
source_dir, before expanding any relative path, will be used (the
typical usage).  The CMakeLists.txt file in the specified source
directory will be processed immediately by CMake before processing in
the current input file continues beyond this command.

If the EXCLUDE_FROM_ALL argument is provided then targets in the
subdirectory will not be included in the ALL target of the parent
directory by default, and will be excluded from IDE project files.
Users must explicitly build targets in the subdirectory.  This is
meant for use when the subdirectory contains a separate part of the
project that is useful but not necessary, such as a set of examples.
Typically the subdirectory should contain its own project() command
invocation so that a full build system will be generated in the
subdirectory (such as a VS IDE solution file).  Note that inter-target
dependencies supercede this exclusion.  If a target built by the
parent project depends on a target in the subdirectory, the dependee
target will be included in the parent project build system to satisfy
the dependency.

add_test
--------

Add a test to the project to be run by ``ctest(1)``.

::

 add_test(NAME <name> COMMAND <command> [<arg>...]
          [CONFIGURATIONS <config>...]
          [WORKING_DIRECTORY <dir>])

Add a test called ``<name>``.  The test name may not contain spaces,
quotes, or other characters special in CMake syntax.  The options are:

``COMMAND``
  Specify the test command-line.  If ``<command>`` specifies an
  executable target (created by ``add_executable()``) it will
  automatically be replaced by the location of the executable created
  at build time.

``CONFIGURATIONS``
  Restrict execution of the test only to the named configurations.

``WORKING_DIRECTORY``
  Set the ``WORKING_DIRECTORY`` test property to
  specify the working directory in which to execute the test.
  If not specified the test will be run with the current working
  directory set to the build directory corresponding to the
  current source directory.

The ``COMMAND`` and ``WORKING_DIRECTORY`` options may use "generator
expressions" with the syntax ``$<...>``.  See the
``cmake-generator-expressions(7)`` manual for available expressions.

Example usage::

 add_test(NAME mytest
          COMMAND testDriver --config $<CONFIGURATION>
                             --exe $<TARGET_FILE:myexe>)

This creates a test ``mytest`` whose command runs a ``testDriver`` tool
passing the configuration name and the full path to the executable
file produced by target ``myexe``.

.. note::

  CMake will generate tests only if the ``enable_testing()``
  command has been invoked.  The ``CTest`` module invokes the
  command automatically when the ``BUILD_TESTING`` option is ``ON``.

---------------------------------------------------------------------

::

 add_test(<name> <command> [<arg>...])

Add a test called ``<name>`` with the given command-line.  Unlike
the above ``NAME`` signature no transformation is performed on the
command-line to support target names or generator expressions.

aux_source_directory
--------------------

Find all source files in a directory.

::

 aux_source_directory(<dir> <variable>)

Collects the names of all the source files in the specified directory
and stores the list in the <variable> provided.  This command is
intended to be used by projects that use explicit template
instantiation.  Template instantiation files can be stored in a
"Templates" subdirectory and collected automatically using this
command to avoid manually listing all instantiations.

It is tempting to use this command to avoid writing the list of source
files for a library or executable target.  While this seems to work,
there is no way for CMake to generate a build system that knows when a
new source file has been added.  Normally the generated build system
knows when it needs to rerun CMake because the CMakeLists.txt file is
modified to add a new source.  When the source is just added to the
directory without modifying this file, one would have to manually
rerun CMake to generate a build system incorporating the new file.

break
-----

Break from an enclosing foreach or while loop.

::

 break()

Breaks from an enclosing foreach loop or while loop

build_command
-------------

Get a command line to build the current project.
This is mainly intended for internal use by the ``CTest`` module.

 build_command(<variable>
               [CONFIGURATION <config>]
               [TARGET <target>]
               [PROJECT_NAME <projname>] # legacy, causes warning
              )

Sets the given ``<variable>`` to a command-line string of the form::

 <cmake> --build . [--config <config>] [--target <target>] [-- -i]

where ``<cmake>`` is the location of the ``cmake(1)`` command-line
tool, and ``<config>`` and ``<target>`` are the values provided to the
``CONFIGURATION`` and ``TARGET`` options, if any.  The trailing ``-- -i``
option is added for Makefile generators.

When invoked, this ``cmake --build`` command line will launch the
underlying build system tool.

 build_command(<cachevariable> <makecommand>)

This second signature is deprecated, but still available for backwards
compatibility.  Use the first signature instead.

It sets the given ``<cachevariable>`` to a command-line string as
above but without the ``--config`` or ``--target`` options.
The ``<makecommand>`` is ignored but should be the full path to
msdev, devenv, nmake, make or one of the end user build tools
for legacy invocations.

.. note::
 In CMake versions prior to 3.0 this command returned a command
 line that directly invokes the native build tool for the current
 generator.  Their implementation of the ``PROJECT_NAME`` option
 had no useful effects, so CMake now warns on use of the option.

cmake_host_system_information
-----------------------------

Query host system specific information.

::

 cmake_host_system_information(RESULT <variable> QUERY <key> ...)

Queries system information of the host system on which cmake runs.
One or more <key> can be provided to select the information to be
queried.  The list of queried values is stored in <variable>.

<key> can be one of the following values:

::

 NUMBER_OF_LOGICAL_CORES   = Number of logical cores.
 NUMBER_OF_PHYSICAL_CORES  = Number of physical cores.
 HOSTNAME                  = Hostname.
 FQDN                      = Fully qualified domain name.
 TOTAL_VIRTUAL_MEMORY      = Total virtual memory in megabytes.
 AVAILABLE_VIRTUAL_MEMORY  = Available virtual memory in megabytes.
 TOTAL_PHYSICAL_MEMORY     = Total physical memory in megabytes.
 AVAILABLE_PHYSICAL_MEMORY = Available physical memory in megabytes.

cmake_minimum_required
----------------------

Set the minimum required version of cmake for a project.

::

 cmake_minimum_required(VERSION major[.minor[.patch[.tweak]]]
                        [FATAL_ERROR])

If the current version of CMake is lower than that required it will
stop processing the project and report an error.  When a version
higher than 2.4 is specified the command implicitly invokes

::

 cmake_policy(VERSION major[.minor[.patch[.tweak]]])

which sets the cmake policy version level to the version specified.
When version 2.4 or lower is given the command implicitly invokes

::

 cmake_policy(VERSION 2.4)

which enables compatibility features for CMake 2.4 and lower.

The FATAL_ERROR option is accepted but ignored by CMake 2.6 and
higher.  It should be specified so CMake versions 2.4 and lower fail
with an error instead of just a warning.

cmake_policy
------------

Manage CMake Policy settings.

As CMake evolves it is sometimes necessary to change existing behavior
in order to fix bugs or improve implementations of existing features.
The CMake Policy mechanism is designed to help keep existing projects
building as new versions of CMake introduce changes in behavior.  Each
new policy (behavioral change) is given an identifier of the form
"CMP<NNNN>" where "<NNNN>" is an integer index.  Documentation
associated with each policy describes the OLD and NEW behavior and the
reason the policy was introduced.  Projects may set each policy to
select the desired behavior.  When CMake needs to know which behavior
to use it checks for a setting specified by the project.  If no
setting is available the OLD behavior is assumed and a warning is
produced requesting that the policy be set.

The cmake_policy command is used to set policies to OLD or NEW
behavior.  While setting policies individually is supported, we
encourage projects to set policies based on CMake versions.

::

 cmake_policy(VERSION major.minor[.patch[.tweak]])

Specify that the current CMake list file is written for the given
version of CMake.  All policies introduced in the specified version or
earlier will be set to use NEW behavior.  All policies introduced
after the specified version will be unset (unless variable
CMAKE_POLICY_DEFAULT_CMP<NNNN> sets a default).  This effectively
requests behavior preferred as of a given CMake version and tells
newer CMake versions to warn about their new policies.  The policy
version specified must be at least 2.4 or the command will report an
error.  In order to get compatibility features supporting versions
earlier than 2.4 see documentation of policy CMP0001.

::

 cmake_policy(SET CMP<NNNN> NEW)
 cmake_policy(SET CMP<NNNN> OLD)

Tell CMake to use the OLD or NEW behavior for a given policy.
Projects depending on the old behavior of a given policy may silence a
policy warning by setting the policy state to OLD.  Alternatively one
may fix the project to work with the new behavior and set the policy
state to NEW.

::

 cmake_policy(GET CMP<NNNN> <variable>)

Check whether a given policy is set to OLD or NEW behavior.  The
output variable value will be "OLD" or "NEW" if the policy is set, and
empty otherwise.

CMake keeps policy settings on a stack, so changes made by the
cmake_policy command affect only the top of the stack.  A new entry on
the policy stack is managed automatically for each subdirectory to
protect its parents and siblings.  CMake also manages a new entry for
scripts loaded by include() and find_package() commands except when
invoked with the NO_POLICY_SCOPE option (see also policy CMP0011).
The cmake_policy command provides an interface to manage custom
entries on the policy stack:

::

 cmake_policy(PUSH)
 cmake_policy(POP)

Each PUSH must have a matching POP to erase any changes.  This is
useful to make temporary changes to policy settings.

Functions and macros record policy settings when they are created and
use the pre-record policies when they are invoked.  If the function or
macro implementation sets policies, the changes automatically
propagate up through callers until they reach the closest nested
policy stack entry.

configure_file
--------------

Copy a file to another location and modify its contents.

::

 configure_file(<input> <output>
                [COPYONLY] [ESCAPE_QUOTES] [@ONLY]
                [NEWLINE_STYLE [UNIX|DOS|WIN32|LF|CRLF] ])

Copies a file <input> to file <output> and substitutes variable values
referenced in the file content.  If <input> is a relative path it is
evaluated with respect to the current source directory.  The <input>
must be a file, not a directory.  If <output> is a relative path it is
evaluated with respect to the current binary directory.  If <output>
names an existing directory the input file is placed in that directory
with its original name.

If the <input> file is modified the build system will re-run CMake to
re-configure the file and generate the build system again.

This command replaces any variables in the input file referenced as
${VAR} or @VAR@ with their values as determined by CMake.  If a
variable is not defined, it will be replaced with nothing.  If
COPYONLY is specified, then no variable expansion will take place.  If
ESCAPE_QUOTES is specified then any substituted quotes will be C-style
escaped.  The file will be configured with the current values of CMake
variables.  If @ONLY is specified, only variables of the form @VAR@
will be replaced and ${VAR} will be ignored.  This is useful for
configuring scripts that use ${VAR}.

Input file lines of the form "#cmakedefine VAR ..." will be replaced
with either "#define VAR ..." or ``/* #undef VAR */`` depending on
whether VAR is set in CMake to any value not considered a false
constant by the if() command.  (Content of "...", if any, is processed
as above.) Input file lines of the form "#cmakedefine01 VAR" will be
replaced with either "#define VAR 1" or "#define VAR 0" similarly.

With NEWLINE_STYLE the line ending could be adjusted:

::

 'UNIX' or 'LF' for \n, 'DOS', 'WIN32' or 'CRLF' for \r\n.

COPYONLY must not be used with NEWLINE_STYLE.

create_test_sourcelist
----------------------

Create a test driver and source list for building test programs.

::

 create_test_sourcelist(sourceListName driverName
                        test1 test2 test3
                        EXTRA_INCLUDE include.h
                        FUNCTION function)

A test driver is a program that links together many small tests into a
single executable.  This is useful when building static executables
with large libraries to shrink the total required size.  The list of
source files needed to build the test driver will be in
sourceListName.  DriverName is the name of the test driver program.
The rest of the arguments consist of a list of test source files, can
be semicolon separated.  Each test source file should have a function
in it that is the same name as the file with no extension (foo.cxx
should have int foo(int, char*[]);) DriverName will be able to call
each of the tests by name on the command line.  If EXTRA_INCLUDE is
specified, then the next argument is included into the generated file.
If FUNCTION is specified, then the next argument is taken as a
function name that is passed a pointer to ac and av.  This can be used
to add extra command line processing to each test.  The cmake variable
CMAKE_TESTDRIVER_BEFORE_TESTMAIN can be set to have code that will be
placed directly before calling the test main function.
CMAKE_TESTDRIVER_AFTER_TESTMAIN can be set to have code that will be
placed directly after the call to the test main function.

define_property
---------------

Define and document custom properties.

::

 define_property(<GLOBAL | DIRECTORY | TARGET | SOURCE |
                  TEST | VARIABLE | CACHED_VARIABLE>
                  PROPERTY <name> [INHERITED]
                  BRIEF_DOCS <brief-doc> [docs...]
                  FULL_DOCS <full-doc> [docs...])

Define one property in a scope for use with the set_property and
get_property commands.  This is primarily useful to associate
documentation with property names that may be retrieved with the
get_property command.  The first argument determines the kind of scope
in which the property should be used.  It must be one of the
following:

::

 GLOBAL    = associated with the global namespace
 DIRECTORY = associated with one directory
 TARGET    = associated with one target
 SOURCE    = associated with one source file
 TEST      = associated with a test named with add_test
 VARIABLE  = documents a CMake language variable
 CACHED_VARIABLE = documents a CMake cache variable

Note that unlike set_property and get_property no actual scope needs
to be given; only the kind of scope is important.

The required PROPERTY option is immediately followed by the name of
the property being defined.

If the INHERITED option then the get_property command will chain up to
the next higher scope when the requested property is not set in the
scope given to the command.  DIRECTORY scope chains to GLOBAL.
TARGET, SOURCE, and TEST chain to DIRECTORY.

The BRIEF_DOCS and FULL_DOCS options are followed by strings to be
associated with the property as its brief and full documentation.
Corresponding options to the get_property command will retrieve the
documentation.

elseif
------

Starts the elseif portion of an if block.

::

 elseif(expression)

See the if command.

else
----

Starts the else portion of an if block.

::

 else(expression)

See the if command.

enable_language
---------------

Enable a language (CXX/C/Fortran/etc)

::

 enable_language(<lang> [OPTIONAL] )

This command enables support for the named language in CMake.  This is
the same as the project command but does not create any of the extra
variables that are created by the project command.  Example languages
are CXX, C, Fortran.

This command must be called in file scope, not in a function call.
Furthermore, it must be called in the highest directory common to all
targets using the named language directly for compiling sources or
indirectly through link dependencies.  It is simplest to enable all
needed languages in the top-level directory of a project.

The OPTIONAL keyword is a placeholder for future implementation and
does not currently work.

enable_testing
--------------

Enable testing for current directory and below.

::

 enable_testing()

Enables testing for this directory and below.  See also the add_test
command.  Note that ctest expects to find a test file in the build
directory root.  Therefore, this command should be in the source
directory root.

endforeach
----------

Ends a list of commands in a FOREACH block.

::

 endforeach(expression)

See the FOREACH command.

endfunction
-----------

Ends a list of commands in a function block.

::

 endfunction(expression)

See the function command.

endif
-----

Ends a list of commands in an if block.

::

 endif(expression)

See the if command.

endmacro
--------

Ends a list of commands in a macro block.

::

 endmacro(expression)

See the macro command.

endwhile
--------

Ends a list of commands in a while block.

::

 endwhile(expression)

See the while command.

execute_process
---------------

Execute one or more child processes.

 execute_process(COMMAND <cmd1> [args1...]]
                 [COMMAND <cmd2> [args2...] [...]]
                 [WORKING_DIRECTORY <directory>]
                 [TIMEOUT <seconds>]
                 [RESULT_VARIABLE <variable>]
                 [OUTPUT_VARIABLE <variable>]
                 [ERROR_VARIABLE <variable>]
                 [INPUT_FILE <file>]
                 [OUTPUT_FILE <file>]
                 [ERROR_FILE <file>]
                 [OUTPUT_QUIET]
                 [ERROR_QUIET]
                 [OUTPUT_STRIP_TRAILING_WHITESPACE]
                 [ERROR_STRIP_TRAILING_WHITESPACE])

Runs the given sequence of one or more commands with the standard
output of each process piped to the standard input of the next.
A single standard error pipe is used for all processes.

Options:

COMMAND
 A child process command line.

 CMake executes the child process using operating system APIs directly.
 All arguments are passed VERBATIM to the child process.
 No intermediate shell is used, so shell operators such as ``>``
 are treated as normal arguments.
 (Use the ``INPUT_*``, ``OUTPUT_*``, and ``ERROR_*`` options to
 redirect stdin, stdout, and stderr.)

WORKING_DIRECTORY
 The named directory will be set as the current working directory of
 the child processes.

TIMEOUT
 The child processes will be terminated if they do not finish in the
 specified number of seconds (fractions are allowed).

RESULT_VARIABLE
 The variable will be set to contain the result of running the processes.
 This will be an integer return code from the last child or a string
 describing an error condition.

OUTPUT_VARIABLE, ERROR_VARIABLE
 The variable named will be set with the contents of the standard output
 and standard error pipes, respectively.  If the same variable is named
 for both pipes their output will be merged in the order produced.

INPUT_FILE, OUTPUT_FILE, ERROR_FILE
 The file named will be attached to the standard input of the first
 process, standard output of the last process, or standard error of
 all processes, respectively.

OUTPUT_QUIET, ERROR_QUIET
 The standard output or standard error results will be quietly ignored.

If more than one ``OUTPUT_*`` or ``ERROR_*`` option is given for the
same pipe the precedence is not specified.
If no ``OUTPUT_*`` or ``ERROR_*`` options are given the output will
be shared with the corresponding pipes of the CMake process itself.

The ``execute_process()`` command is a newer more powerful version of
``exec_program()``, but the old command has been kept for compatibility.
Both commands run while CMake is processing the project prior to build
system generation.  Use ``add_custom_target()`` and
``add_custom_command()`` to create custom commands that run at
build time.

export
------

Export targets from the build tree for use by outside projects.

::

 export(EXPORT <export-name> [NAMESPACE <namespace>] [FILE <filename>])

Create a file <filename> that may be included by outside projects to
import targets from the current project's build tree.  This is useful
during cross-compiling to build utility executables that can run on
the host platform in one project and then import them into another
project being compiled for the target platform.  If the NAMESPACE
option is given the <namespace> string will be prepended to all target
names written to the file.

Target installations are associated with the export <export-name>
using the ``EXPORT`` option of the ``install(TARGETS)`` command.

The file created by this command is specific to the build tree and
should never be installed.  See the install(EXPORT) command to export
targets from an installation tree.

The properties set on the generated IMPORTED targets will have the
same values as the final values of the input TARGETS.

::

 export(TARGETS [target1 [target2 [...]]] [NAMESPACE <namespace>]
        [APPEND] FILE <filename> [EXPORT_LINK_INTERFACE_LIBRARIES])

This signature is similar to the ``EXPORT`` signature, but targets are listed
explicitly rather than specified as an export-name.  If the APPEND option is
given the generated code will be appended to the file instead of overwriting it.
The EXPORT_LINK_INTERFACE_LIBRARIES keyword, if present, causes the
contents of the properties matching
``(IMPORTED_)?LINK_INTERFACE_LIBRARIES(_<CONFIG>)?`` to be exported, when
policy CMP0022 is NEW.  If a library target is included in the export
but a target to which it links is not included the behavior is
unspecified.

::

 export(PACKAGE <name>)

Store the current build directory in the CMake user package registry
for package <name>.  The find_package command may consider the
directory while searching for package <name>.  This helps dependent
projects find and use a package from the current project's build tree
without help from the user.  Note that the entry in the package
registry that this command creates works only in conjunction with a
package configuration file (<name>Config.cmake) that works with the
build tree.

file
----

File manipulation command.

::

 file(WRITE filename "message to write"... )
 file(APPEND filename "message to write"... )
 file(READ filename variable [LIMIT numBytes] [OFFSET offset] [HEX])
 file(<MD5|SHA1|SHA224|SHA256|SHA384|SHA512> filename variable)
 file(STRINGS filename variable [LIMIT_COUNT num]
      [LIMIT_INPUT numBytes] [LIMIT_OUTPUT numBytes]
      [LENGTH_MINIMUM numBytes] [LENGTH_MAXIMUM numBytes]
      [NEWLINE_CONSUME] [REGEX regex]
      [NO_HEX_CONVERSION])
 file(GLOB variable [RELATIVE path] [globbing expressions]...)
 file(GLOB_RECURSE variable [RELATIVE path]
      [FOLLOW_SYMLINKS] [globbing expressions]...)
 file(RENAME <oldname> <newname>)
 file(REMOVE [file1 ...])
 file(REMOVE_RECURSE [file1 ...])
 file(MAKE_DIRECTORY [directory1 directory2 ...])
 file(RELATIVE_PATH variable directory file)
 file(TO_CMAKE_PATH path result)
 file(TO_NATIVE_PATH path result)
 file(DOWNLOAD url file [INACTIVITY_TIMEOUT timeout]
      [TIMEOUT timeout] [STATUS status] [LOG log] [SHOW_PROGRESS]
      [EXPECTED_HASH ALGO=value] [EXPECTED_MD5 sum]
      [TLS_VERIFY on|off] [TLS_CAINFO file])
 file(UPLOAD filename url [INACTIVITY_TIMEOUT timeout]
      [TIMEOUT timeout] [STATUS status] [LOG log] [SHOW_PROGRESS])
 file(TIMESTAMP filename variable [<format string>] [UTC])
 file(GENERATE OUTPUT output_file
      <INPUT input_file|CONTENT input_content>
      [CONDITION expression])

WRITE will write a message into a file called 'filename'.  It
overwrites the file if it already exists, and creates the file if it
does not exist.  (If the file is a build input, use configure_file to
update the file only when its content changes.)

APPEND will write a message into a file same as WRITE, except it will
append it to the end of the file

READ will read the content of a file and store it into the variable.
It will start at the given offset and read up to numBytes.  If the
argument HEX is given, the binary data will be converted to
hexadecimal representation and this will be stored in the variable.

MD5, SHA1, SHA224, SHA256, SHA384, and SHA512 will compute a
cryptographic hash of the content of a file.

STRINGS will parse a list of ASCII strings from a file and store it in
a variable.  Binary data in the file are ignored.  Carriage return
(CR) characters are ignored.  It works also for Intel Hex and Motorola
S-record files, which are automatically converted to binary format
when reading them.  Disable this using NO_HEX_CONVERSION.

LIMIT_COUNT sets the maximum number of strings to return.  LIMIT_INPUT
sets the maximum number of bytes to read from the input file.
LIMIT_OUTPUT sets the maximum number of bytes to store in the output
variable.  LENGTH_MINIMUM sets the minimum length of a string to
return.  Shorter strings are ignored.  LENGTH_MAXIMUM sets the maximum
length of a string to return.  Longer strings are split into strings
no longer than the maximum length.  NEWLINE_CONSUME allows newlines to
be included in strings instead of terminating them.

REGEX specifies a regular expression that a string must match to be
returned.  Typical usage

::

 file(STRINGS myfile.txt myfile)

stores a list in the variable "myfile" in which each item is a line
from the input file.

GLOB will generate a list of all files that match the globbing
expressions and store it into the variable.  Globbing expressions are
similar to regular expressions, but much simpler.  If RELATIVE flag is
specified for an expression, the results will be returned as a
relative path to the given path.  (We do not recommend using GLOB to
collect a list of source files from your source tree.  If no
CMakeLists.txt file changes when a source is added or removed then the
generated build system cannot know when to ask CMake to regenerate.)

Examples of globbing expressions include:

::

 *.cxx      - match all files with extension cxx
 *.vt?      - match all files with extension vta,...,vtz
 f[3-5].txt - match files f3.txt, f4.txt, f5.txt

GLOB_RECURSE will generate a list similar to the regular GLOB, except
it will traverse all the subdirectories of the matched directory and
match the files.  Subdirectories that are symlinks are only traversed
if FOLLOW_SYMLINKS is given or cmake policy CMP0009 is not set to NEW.
See cmake --help-policy CMP0009 for more information.

Examples of recursive globbing include:

::

 /dir/*.py  - match all python files in /dir and subdirectories

MAKE_DIRECTORY will create the given directories, also if their parent
directories don't exist yet

RENAME moves a file or directory within a filesystem, replacing the
destination atomically.

REMOVE will remove the given files, also in subdirectories

REMOVE_RECURSE will remove the given files and directories, also
non-empty directories

RELATIVE_PATH will determine relative path from directory to the given
file.

TO_CMAKE_PATH will convert path into a cmake style path with unix /.
The input can be a single path or a system path like "$ENV{PATH}".
Note the double quotes around the ENV call TO_CMAKE_PATH only takes
one argument.  This command will also convert the native list
delimiters for a list of paths like the PATH environment variable.

TO_NATIVE_PATH works just like TO_CMAKE_PATH, but will convert from a
cmake style path into the native path style \ for windows and / for
UNIX.

DOWNLOAD will download the given URL to the given file.  If LOG var is
specified a log of the download will be put in var.  If STATUS var is
specified the status of the operation will be put in var.  The status
is returned in a list of length 2.  The first element is the numeric
return value for the operation, and the second element is a string
value for the error.  A 0 numeric error means no error in the
operation.  If TIMEOUT time is specified, the operation will timeout
after time seconds, time should be specified as an integer.  The
INACTIVITY_TIMEOUT specifies an integer number of seconds of
inactivity after which the operation should terminate.  If
EXPECTED_HASH ALGO=value is specified, the operation will verify that
the downloaded file's actual hash matches the expected value, where
ALGO is one of MD5, SHA1, SHA224, SHA256, SHA384, or SHA512.  If it
does not match, the operation fails with an error.  ("EXPECTED_MD5
sum" is short-hand for "EXPECTED_HASH MD5=sum".) If SHOW_PROGRESS is
specified, progress information will be printed as status messages
until the operation is complete.  For https URLs CMake must be built
with OpenSSL.  TLS/SSL certificates are not checked by default.  Set
TLS_VERIFY to ON to check certificates and/or use EXPECTED_HASH to
verify downloaded content.  Set TLS_CAINFO to specify a custom
Certificate Authority file.  If either TLS option is not given CMake
will check variables CMAKE_TLS_VERIFY and CMAKE_TLS_CAINFO,
respectively.

UPLOAD will upload the given file to the given URL.  If LOG var is
specified a log of the upload will be put in var.  If STATUS var is
specified the status of the operation will be put in var.  The status
is returned in a list of length 2.  The first element is the numeric
return value for the operation, and the second element is a string
value for the error.  A 0 numeric error means no error in the
operation.  If TIMEOUT time is specified, the operation will timeout
after time seconds, time should be specified as an integer.  The
INACTIVITY_TIMEOUT specifies an integer number of seconds of
inactivity after which the operation should terminate.  If
SHOW_PROGRESS is specified, progress information will be printed as
status messages until the operation is complete.

TIMESTAMP will write a string representation of the modification time
of filename to variable.

Should the command be unable to obtain a timestamp variable will be
set to the empty string "".

See documentation of the string TIMESTAMP sub-command for more
details.

The file() command also provides COPY and INSTALL signatures:

::

 file(<COPY|INSTALL> files... DESTINATION <dir>
      [FILE_PERMISSIONS permissions...]
      [DIRECTORY_PERMISSIONS permissions...]
      [NO_SOURCE_PERMISSIONS] [USE_SOURCE_PERMISSIONS]
      [FILES_MATCHING]
      [[PATTERN <pattern> | REGEX <regex>]
       [EXCLUDE] [PERMISSIONS permissions...]] [...])

The COPY signature copies files, directories, and symlinks to a
destination folder.  Relative input paths are evaluated with respect
to the current source directory, and a relative destination is
evaluated with respect to the current build directory.  Copying
preserves input file timestamps, and optimizes out a file if it exists
at the destination with the same timestamp.  Copying preserves input
permissions unless explicit permissions or NO_SOURCE_PERMISSIONS are
given (default is USE_SOURCE_PERMISSIONS).  See the install(DIRECTORY)
command for documentation of permissions, PATTERN, REGEX, and EXCLUDE
options.

The INSTALL signature differs slightly from COPY: it prints status
messages, and NO_SOURCE_PERMISSIONS is default.  Installation scripts
generated by the install() command use this signature (with some
undocumented options for internal use).

GENERATE will write an <output_file> with content from an
<input_file>, or from <input_content>.  The output is generated
conditionally based on the content of the <condition>.  The file is
written at CMake generate-time and the input may contain generator
expressions.  The <condition>, <output_file> and <input_file> may also
contain generator expressions.  The <condition> must evaluate to
either '0' or '1'.  The <output_file> must evaluate to a unique name
among all configurations and among all invocations of file(GENERATE).

find_file
---------

A short-hand signature is:

 find_file (<VAR> name1 [path1 path2 ...])

The general signature is:

 find_file (
           <VAR>
           name | NAMES name1 [name2 ...]
           [HINTS path1 [path2 ... ENV var]]
           [PATHS path1 [path2 ... ENV var]]
           [PATH_SUFFIXES suffix1 [suffix2 ...]]
           [DOC "cache documentation string"]
           [NO_DEFAULT_PATH]
           [NO_CMAKE_ENVIRONMENT_PATH]
           [NO_CMAKE_PATH]
           [NO_SYSTEM_ENVIRONMENT_PATH]
           [NO_CMAKE_SYSTEM_PATH]
           [CMAKE_FIND_ROOT_PATH_BOTH |
            ONLY_CMAKE_FIND_ROOT_PATH |
            NO_CMAKE_FIND_ROOT_PATH]
          )

This command is used to find a full path to named file.
A cache entry named by ``<VAR>`` is created to store the result
of this command.
If the full path to a file is found the result is stored in the variable
and the search will not be repeated unless the variable is cleared.
If nothing is found, the result will be
``<VAR>-NOTFOUND``, and the search will be attempted again the
next time find_file is invoked with the same variable.
The name of the full path to a file that
is searched for is specified by the names listed
after the NAMES argument.   Additional search locations
can be specified after the PATHS argument.  If ENV var is
found in the HINTS or PATHS section the environment variable var
will be read and converted from a system environment variable to
a cmake style list of paths.  For example ENV PATH would be a way
to list the system path variable. The argument
after DOC will be used for the documentation string in
the cache.
PATH_SUFFIXES specifies additional subdirectories to check below
each search path.

If NO_DEFAULT_PATH is specified, then no additional paths are
added to the search.
If NO_DEFAULT_PATH is not specified, the search process is as follows:

1. Search paths specified in cmake-specific cache variables.
   These are intended to be used on the command line with a -DVAR=value.
   This can be skipped if NO_CMAKE_PATH is passed.

   * <prefix>/include/<arch> if CMAKE_LIBRARY_ARCHITECTURE is set, and <prefix>/include for each <prefix> in CMAKE_PREFIX_PATH
   * CMAKE_INCLUDE_PATH
   * CMAKE_FRAMEWORK_PATH

2. Search paths specified in cmake-specific environment variables.
   These are intended to be set in the user's shell configuration.
   This can be skipped if NO_CMAKE_ENVIRONMENT_PATH is passed.

   * <prefix>/include/<arch> if CMAKE_LIBRARY_ARCHITECTURE is set, and <prefix>/include for each <prefix> in CMAKE_PREFIX_PATH
   * CMAKE_INCLUDE_PATH
   * CMAKE_FRAMEWORK_PATH

3. Search the paths specified by the HINTS option.
   These should be paths computed by system introspection, such as a
   hint provided by the location of another item already found.
   Hard-coded guesses should be specified with the PATHS option.

4. Search the standard system environment variables.
   This can be skipped if NO_SYSTEM_ENVIRONMENT_PATH is an argument.

   * PATH and INCLUDE

5. Search cmake variables defined in the Platform files
   for the current system.  This can be skipped if NO_CMAKE_SYSTEM_PATH
   is passed.

   * <prefix>/include/<arch> if CMAKE_LIBRARY_ARCHITECTURE is set, and <prefix>/include for each <prefix> in CMAKE_SYSTEM_PREFIX_PATH
   * CMAKE_SYSTEM_INCLUDE_PATH
   * CMAKE_SYSTEM_FRAMEWORK_PATH

6. Search the paths specified by the PATHS option
   or in the short-hand version of the command.
   These are typically hard-coded guesses.

On Darwin or systems supporting OS X Frameworks, the cmake variable
CMAKE_FIND_FRAMEWORK can be set to empty or one of the following:

* FIRST: Try to find frameworks before standard libraries or headers.
  This is the default on Darwin.

* LAST: Try to find frameworks after standard libraries or headers.

* ONLY: Only try to find frameworks.

* NEVER: Never try to find frameworks.

On Darwin or systems supporting OS X Application Bundles, the cmake
variable CMAKE_FIND_APPBUNDLE can be set to empty or one of the
following:

* FIRST: Try to find application bundles before standard programs.
  This is the default on Darwin.

* LAST: Try to find application bundles after standard programs.

* ONLY: Only try to find application bundles.

* NEVER: Never try to find application bundles.

The CMake variable ``CMAKE_FIND_ROOT_PATH`` specifies one or more
directories to be prepended to all other search directories.  This
effectively "re-roots" the entire search under given locations.
Paths which are descendants of the ``CMAKE_STAGING_PREFIX`` are excluded
from this re-rooting, because that variable is always a path on the host system.
By default the ``CMAKE_FIND_ROOT_PATH`` is empty.

The ``CMAKE_SYSROOT`` variable can also be used to specify exactly one
directory to use as a prefix.  Setting ``CMAKE_SYSROOT`` also has other
effects.  See the documentation for that variable for more.

These variables are especially useful when cross-compiling to
point to the root directory of the target environment and CMake will
search there too.  By default at first the directories listed in
``CMAKE_FIND_ROOT_PATH`` are searched, then the ``CMAKE_SYSROOT``
directory is searched, and then the non-rooted directories will be
searched.  The default behavior can be adjusted by setting
``CMAKE_FIND_ROOT_PATH_MODE_INCLUDE``.  This behavior can be manually
overridden on a per-call basis.  By using CMAKE_FIND_ROOT_PATH_BOTH
the search order will be as described above.  If
NO_CMAKE_FIND_ROOT_PATH is used then ``CMAKE_FIND_ROOT_PATH`` will not be
used.  If ONLY_CMAKE_FIND_ROOT_PATH is used then only the re-rooted
directories and directories below ``CMAKE_STAGING_PREFIX`` will be searched.

The default search order is designed to be most-specific to
least-specific for common use cases.
Projects may override the order by simply calling the command
multiple times and using the ``NO_*`` options:

 find_file (<VAR> NAMES name PATHS paths... NO_DEFAULT_PATH)
 find_file (<VAR> NAMES name)

Once one of the calls succeeds the result variable will be set
and stored in the cache so that no call will search again.

find_library
------------

A short-hand signature is:

 find_library (<VAR> name1 [path1 path2 ...])

The general signature is:

 find_library (
           <VAR>
           name | NAMES name1 [name2 ...] [NAMES_PER_DIR]
           [HINTS path1 [path2 ... ENV var]]
           [PATHS path1 [path2 ... ENV var]]
           [PATH_SUFFIXES suffix1 [suffix2 ...]]
           [DOC "cache documentation string"]
           [NO_DEFAULT_PATH]
           [NO_CMAKE_ENVIRONMENT_PATH]
           [NO_CMAKE_PATH]
           [NO_SYSTEM_ENVIRONMENT_PATH]
           [NO_CMAKE_SYSTEM_PATH]
           [CMAKE_FIND_ROOT_PATH_BOTH |
            ONLY_CMAKE_FIND_ROOT_PATH |
            NO_CMAKE_FIND_ROOT_PATH]
          )

This command is used to find a library.
A cache entry named by ``<VAR>`` is created to store the result
of this command.
If the library is found the result is stored in the variable
and the search will not be repeated unless the variable is cleared.
If nothing is found, the result will be
``<VAR>-NOTFOUND``, and the search will be attempted again the
next time find_library is invoked with the same variable.
The name of the library that
is searched for is specified by the names listed
after the NAMES argument.   Additional search locations
can be specified after the PATHS argument.  If ENV var is
found in the HINTS or PATHS section the environment variable var
will be read and converted from a system environment variable to
a cmake style list of paths.  For example ENV PATH would be a way
to list the system path variable. The argument
after DOC will be used for the documentation string in
the cache.
PATH_SUFFIXES specifies additional subdirectories to check below
each search path.

If NO_DEFAULT_PATH is specified, then no additional paths are
added to the search.
If NO_DEFAULT_PATH is not specified, the search process is as follows:

1. Search paths specified in cmake-specific cache variables.
   These are intended to be used on the command line with a -DVAR=value.
   This can be skipped if NO_CMAKE_PATH is passed.

   * <prefix>/lib/<arch> if CMAKE_LIBRARY_ARCHITECTURE is set, and <prefix>/lib for each <prefix> in CMAKE_PREFIX_PATH
   * CMAKE_LIBRARY_PATH
   * CMAKE_FRAMEWORK_PATH

2. Search paths specified in cmake-specific environment variables.
   These are intended to be set in the user's shell configuration.
   This can be skipped if NO_CMAKE_ENVIRONMENT_PATH is passed.

   * <prefix>/lib/<arch> if CMAKE_LIBRARY_ARCHITECTURE is set, and <prefix>/lib for each <prefix> in CMAKE_PREFIX_PATH
   * CMAKE_LIBRARY_PATH
   * CMAKE_FRAMEWORK_PATH

3. Search the paths specified by the HINTS option.
   These should be paths computed by system introspection, such as a
   hint provided by the location of another item already found.
   Hard-coded guesses should be specified with the PATHS option.

4. Search the standard system environment variables.
   This can be skipped if NO_SYSTEM_ENVIRONMENT_PATH is an argument.

   * PATH and LIB

5. Search cmake variables defined in the Platform files
   for the current system.  This can be skipped if NO_CMAKE_SYSTEM_PATH
   is passed.

   * <prefix>/lib/<arch> if CMAKE_LIBRARY_ARCHITECTURE is set, and <prefix>/lib for each <prefix> in CMAKE_SYSTEM_PREFIX_PATH
   * CMAKE_SYSTEM_LIBRARY_PATH
   * CMAKE_SYSTEM_FRAMEWORK_PATH

6. Search the paths specified by the PATHS option
   or in the short-hand version of the command.
   These are typically hard-coded guesses.

On Darwin or systems supporting OS X Frameworks, the cmake variable
CMAKE_FIND_FRAMEWORK can be set to empty or one of the following:

* FIRST: Try to find frameworks before standard libraries or headers.
  This is the default on Darwin.

* LAST: Try to find frameworks after standard libraries or headers.

* ONLY: Only try to find frameworks.

* NEVER: Never try to find frameworks.

On Darwin or systems supporting OS X Application Bundles, the cmake
variable CMAKE_FIND_APPBUNDLE can be set to empty or one of the
following:

* FIRST: Try to find application bundles before standard programs.
  This is the default on Darwin.

* LAST: Try to find application bundles after standard programs.

* ONLY: Only try to find application bundles.

* NEVER: Never try to find application bundles.

The CMake variable ``CMAKE_FIND_ROOT_PATH`` specifies one or more
directories to be prepended to all other search directories.  This
effectively "re-roots" the entire search under given locations.
Paths which are descendants of the ``CMAKE_STAGING_PREFIX`` are excluded
from this re-rooting, because that variable is always a path on the host system.
By default the ``CMAKE_FIND_ROOT_PATH`` is empty.

The ``CMAKE_SYSROOT`` variable can also be used to specify exactly one
directory to use as a prefix.  Setting ``CMAKE_SYSROOT`` also has other
effects.  See the documentation for that variable for more.

These variables are especially useful when cross-compiling to
point to the root directory of the target environment and CMake will
search there too.  By default at first the directories listed in
``CMAKE_FIND_ROOT_PATH`` are searched, then the ``CMAKE_SYSROOT``
directory is searched, and then the non-rooted directories will be
searched.  The default behavior can be adjusted by setting
``CMAKE_FIND_ROOT_PATH_MODE_LIBRARY``.  This behavior can be manually
overridden on a per-call basis.  By using CMAKE_FIND_ROOT_PATH_BOTH
the search order will be as described above.  If
NO_CMAKE_FIND_ROOT_PATH is used then ``CMAKE_FIND_ROOT_PATH`` will not be
used.  If ONLY_CMAKE_FIND_ROOT_PATH is used then only the re-rooted
directories and directories below ``CMAKE_STAGING_PREFIX`` will be searched.

The default search order is designed to be most-specific to
least-specific for common use cases.
Projects may override the order by simply calling the command
multiple times and using the ``NO_*`` options:

 find_library (<VAR> NAMES name PATHS paths... NO_DEFAULT_PATH)
 find_library (<VAR> NAMES name)

Once one of the calls succeeds the result variable will be set
and stored in the cache so that no call will search again.

When more than one value is given to the NAMES option this command by
default will consider one name at a time and search every directory
for it.  The NAMES_PER_DIR option tells this command to consider one
directory at a time and search for all names in it.

If the library found is a framework, then VAR will be set to the full
path to the framework <fullPath>/A.framework.  When a full path to a
framework is used as a library, CMake will use a -framework A, and a
-F<fullPath> to link the framework to the target.

If the global property FIND_LIBRARY_USE_LIB64_PATHS is set all search
paths will be tested as normal, with "64/" appended, and with all
matches of "lib/" replaced with "lib64/".  This property is
automatically set for the platforms that are known to need it if at
least one of the languages supported by the PROJECT command is
enabled.

find_package
------------

Load settings for an external project.

::

 find_package(<package> [version] [EXACT] [QUIET] [MODULE]
              [REQUIRED] [[COMPONENTS] [components...]]
              [OPTIONAL_COMPONENTS components...]
              [NO_POLICY_SCOPE])

Finds and loads settings from an external project.  ``<package>_FOUND``
will be set to indicate whether the package was found.  When the
package is found package-specific information is provided through
variables and :ref:`Imported Targets` documented by the package itself.  The
``QUIET`` option disables messages if the package cannot be found.  The
``MODULE`` option disables the second signature documented below.  The
``REQUIRED`` option stops processing with an error message if the package
cannot be found.

A package-specific list of required components may be listed after the
``COMPONENTS`` option (or after the ``REQUIRED`` option if present).
Additional optional components may be listed after
``OPTIONAL_COMPONENTS``.  Available components and their influence on
whether a package is considered to be found are defined by the target
package.

The ``[version]`` argument requests a version with which the package found
should be compatible (format is ``major[.minor[.patch[.tweak]]]``).  The
``EXACT`` option requests that the version be matched exactly.  If no
``[version]`` and/or component list is given to a recursive invocation
inside a find-module, the corresponding arguments are forwarded
automatically from the outer call (including the ``EXACT`` flag for
``[version]``).  Version support is currently provided only on a
package-by-package basis (details below).

User code should generally look for packages using the above simple
signature.  The remainder of this command documentation specifies the
full command signature and details of the search process.  Project
maintainers wishing to provide a package to be found by this command
are encouraged to read on.

The command has two modes by which it searches for packages: "Module"
mode and "Config" mode.  Module mode is available when the command is
invoked with the above reduced signature.  CMake searches for a file
called ``Find<package>.cmake`` in the ``CMAKE_MODULE_PATH``
followed by the CMake installation.  If the file is found, it is read
and processed by CMake.  It is responsible for finding the package,
checking the version, and producing any needed messages.  Many
find-modules provide limited or no support for versioning; check
the module documentation.  If no module is found and the ``MODULE``
option is not given the command proceeds to Config mode.

The complete Config mode command signature is::

 find_package(<package> [version] [EXACT] [QUIET]
              [REQUIRED] [[COMPONENTS] [components...]]
              [CONFIG|NO_MODULE]
              [NO_POLICY_SCOPE]
              [NAMES name1 [name2 ...]]
              [CONFIGS config1 [config2 ...]]
              [HINTS path1 [path2 ... ]]
              [PATHS path1 [path2 ... ]]
              [PATH_SUFFIXES suffix1 [suffix2 ...]]
              [NO_DEFAULT_PATH]
              [NO_CMAKE_ENVIRONMENT_PATH]
              [NO_CMAKE_PATH]
              [NO_SYSTEM_ENVIRONMENT_PATH]
              [NO_CMAKE_PACKAGE_REGISTRY]
              [NO_CMAKE_BUILDS_PATH]
              [NO_CMAKE_SYSTEM_PATH]
              [NO_CMAKE_SYSTEM_PACKAGE_REGISTRY]
              [CMAKE_FIND_ROOT_PATH_BOTH |
               ONLY_CMAKE_FIND_ROOT_PATH |
               NO_CMAKE_FIND_ROOT_PATH])

The ``CONFIG`` option may be used to skip Module mode explicitly and
switch to Config mode.  It is synonymous to using ``NO_MODULE``.  Config
mode is also implied by use of options not specified in the reduced
signature.

Config mode attempts to locate a configuration file provided by the
package to be found.  A cache entry called ``<package>_DIR`` is created to
hold the directory containing the file.  By default the command
searches for a package with the name ``<package>``.  If the ``NAMES`` option
is given the names following it are used instead of ``<package>``.  The
command searches for a file called ``<name>Config.cmake`` or
``<lower-case-name>-config.cmake`` for each name specified.  A
replacement set of possible configuration file names may be given
using the ``CONFIGS`` option.  The search procedure is specified below.
Once found, the configuration file is read and processed by CMake.
Since the file is provided by the package it already knows the
location of package contents.  The full path to the configuration file
is stored in the cmake variable ``<package>_CONFIG``.

All configuration files which have been considered by CMake while
searching for an installation of the package with an appropriate
version are stored in the cmake variable ``<package>_CONSIDERED_CONFIGS``,
the associated versions in ``<package>_CONSIDERED_VERSIONS``.

If the package configuration file cannot be found CMake will generate
an error describing the problem unless the ``QUIET`` argument is
specified.  If ``REQUIRED`` is specified and the package is not found a
fatal error is generated and the configure step stops executing.  If
``<package>_DIR`` has been set to a directory not containing a
configuration file CMake will ignore it and search from scratch.

When the ``[version]`` argument is given Config mode will only find a
version of the package that claims compatibility with the requested
version (format is ``major[.minor[.patch[.tweak]]]``).  If the ``EXACT``
option is given only a version of the package claiming an exact match
of the requested version may be found.  CMake does not establish any
convention for the meaning of version numbers.  Package version
numbers are checked by "version" files provided by the packages
themselves.  For a candidate package configuration file
``<config-file>.cmake`` the corresponding version file is located next
to it and named either ``<config-file>-version.cmake`` or
``<config-file>Version.cmake``.  If no such version file is available
then the configuration file is assumed to not be compatible with any
requested version.  A basic version file containing generic version
matching code can be created using the
``CMakePackageConfigHelpers`` module.  When a version file
is found it is loaded to check the requested version number.  The
version file is loaded in a nested scope in which the following
variables have been defined:

``PACKAGE_FIND_NAME``
  the ``<package>`` name
``PACKAGE_FIND_VERSION``
  full requested version string
``PACKAGE_FIND_VERSION_MAJOR``
  major version if requested, else 0
``PACKAGE_FIND_VERSION_MINOR``
  minor version if requested, else 0
``PACKAGE_FIND_VERSION_PATCH``
  patch version if requested, else 0
``PACKAGE_FIND_VERSION_TWEAK``
  tweak version if requested, else 0
``PACKAGE_FIND_VERSION_COUNT``
  number of version components, 0 to 4

The version file checks whether it satisfies the requested version and
sets these variables:

``PACKAGE_VERSION``
  full provided version string
``PACKAGE_VERSION_EXACT``
  true if version is exact match
``PACKAGE_VERSION_COMPATIBLE``
  true if version is compatible
``PACKAGE_VERSION_UNSUITABLE``
  true if unsuitable as any version

These variables are checked by the ``find_package`` command to determine
whether the configuration file provides an acceptable version.  They
are not available after the find_package call returns.  If the version
is acceptable the following variables are set:

``<package>_VERSION``
  full provided version string
``<package>_VERSION_MAJOR``
  major version if provided, else 0
``<package>_VERSION_MINOR``
  minor version if provided, else 0
``<package>_VERSION_PATCH``
  patch version if provided, else 0
``<package>_VERSION_TWEAK``
  tweak version if provided, else 0
``<package>_VERSION_COUNT``
  number of version components, 0 to 4

and the corresponding package configuration file is loaded.  When
multiple package configuration files are available whose version files
claim compatibility with the version requested it is unspecified which
one is chosen.  No attempt is made to choose a highest or closest
version number.

Config mode provides an elaborate interface and search procedure.
Much of the interface is provided for completeness and for use
internally by find-modules loaded by Module mode.  Most user code
should simply call::

 find_package(<package> [major[.minor]] [EXACT] [REQUIRED|QUIET])

in order to find a package.  Package maintainers providing CMake
package configuration files are encouraged to name and install them
such that the procedure outlined below will find them without
requiring use of additional options.

CMake constructs a set of possible installation prefixes for the
package.  Under each prefix several directories are searched for a
configuration file.  The tables below show the directories searched.
Each entry is meant for installation trees following Windows (W), UNIX
(U), or Apple (A) conventions::

 <prefix>/                                               (W)
 <prefix>/(cmake|CMake)/                                 (W)
 <prefix>/<name>*/                                       (W)
 <prefix>/<name>*/(cmake|CMake)/                         (W)
 <prefix>/(lib/<arch>|lib|share)/cmake/<name>*/          (U)
 <prefix>/(lib/<arch>|lib|share)/<name>*/                (U)
 <prefix>/(lib/<arch>|lib|share)/<name>*/(cmake|CMake)/  (U)

On systems supporting OS X Frameworks and Application Bundles the
following directories are searched for frameworks or bundles
containing a configuration file::

 <prefix>/<name>.framework/Resources/                    (A)
 <prefix>/<name>.framework/Resources/CMake/              (A)
 <prefix>/<name>.framework/Versions/*/Resources/         (A)
 <prefix>/<name>.framework/Versions/*/Resources/CMake/   (A)
 <prefix>/<name>.app/Contents/Resources/                 (A)
 <prefix>/<name>.app/Contents/Resources/CMake/           (A)

In all cases the ``<name>`` is treated as case-insensitive and corresponds
to any of the names specified (``<package>`` or names given by ``NAMES``).
Paths with ``lib/<arch>`` are enabled if the
``CMAKE_LIBRARY_ARCHITECTURE`` variable is set.  If ``PATH_SUFFIXES``
is specified the suffixes are appended to each (W) or (U) directory entry
one-by-one.

This set of directories is intended to work in cooperation with
projects that provide configuration files in their installation trees.
Directories above marked with (W) are intended for installations on
Windows where the prefix may point at the top of an application's
installation directory.  Those marked with (U) are intended for
installations on UNIX platforms where the prefix is shared by multiple
packages.  This is merely a convention, so all (W) and (U) directories
are still searched on all platforms.  Directories marked with (A) are
intended for installations on Apple platforms.  The cmake variables
``CMAKE_FIND_FRAMEWORK`` and ``CMAKE_FIND_APPBUNDLE``
determine the order of preference as specified below.

The set of installation prefixes is constructed using the following
steps.  If ``NO_DEFAULT_PATH`` is specified all ``NO_*`` options are
enabled.

1. Search paths specified in cmake-specific cache variables.  These
   are intended to be used on the command line with a ``-DVAR=value``.
   This can be skipped if ``NO_CMAKE_PATH`` is passed::

 CMAKE_PREFIX_PATH
 CMAKE_FRAMEWORK_PATH
 CMAKE_APPBUNDLE_PATH

2. Search paths specified in cmake-specific environment variables.
   These are intended to be set in the user's shell configuration.
   This can be skipped if ``NO_CMAKE_ENVIRONMENT_PATH`` is passed::

 <package>_DIR
 CMAKE_PREFIX_PATH
 CMAKE_FRAMEWORK_PATH
 CMAKE_APPBUNDLE_PATH

3. Search paths specified by the ``HINTS`` option.  These should be paths
   computed by system introspection, such as a hint provided by the
   location of another item already found.  Hard-coded guesses should
   be specified with the ``PATHS`` option.

4. Search the standard system environment variables.  This can be
   skipped if ``NO_SYSTEM_ENVIRONMENT_PATH`` is passed.  Path entries
   ending in ``/bin`` or ``/sbin`` are automatically converted to their
   parent directories::

 PATH

5. Search project build trees recently configured in a ``cmake-gui(1)``.
   This can be skipped if ``NO_CMAKE_BUILDS_PATH`` is passed.  It is intended
   for the case when a user is building multiple dependent projects one
   after another.
   (This step is implemented only on Windows.)

6. Search paths stored in the CMake :ref:`User Package Registry`.
   This can be skipped if ``NO_CMAKE_PACKAGE_REGISTRY`` is passed.
   See the ``cmake-packages(7)`` manual for details on the user
   package registry.

7. Search cmake variables defined in the Platform files for the
   current system.  This can be skipped if ``NO_CMAKE_SYSTEM_PATH`` is
   passed::

 CMAKE_SYSTEM_PREFIX_PATH
 CMAKE_SYSTEM_FRAMEWORK_PATH
 CMAKE_SYSTEM_APPBUNDLE_PATH

8. Search paths stored in the CMake :ref:`System Package Registry`.
   This can be skipped if ``NO_CMAKE_SYSTEM_PACKAGE_REGISTRY`` is passed.
   See the ``cmake-packages(7)`` manual for details on the system
   package registry.

9. Search paths specified by the ``PATHS`` option.  These are typically
   hard-coded guesses.

On Darwin or systems supporting OS X Frameworks, the cmake variable
CMAKE_FIND_FRAMEWORK can be set to empty or one of the following:

* FIRST: Try to find frameworks before standard libraries or headers.
  This is the default on Darwin.

* LAST: Try to find frameworks after standard libraries or headers.

* ONLY: Only try to find frameworks.

* NEVER: Never try to find frameworks.

On Darwin or systems supporting OS X Application Bundles, the cmake
variable CMAKE_FIND_APPBUNDLE can be set to empty or one of the
following:

* FIRST: Try to find application bundles before standard programs.
  This is the default on Darwin.

* LAST: Try to find application bundles after standard programs.

* ONLY: Only try to find application bundles.

* NEVER: Never try to find application bundles.

The CMake variable ``CMAKE_FIND_ROOT_PATH`` specifies one or more
directories to be prepended to all other search directories.  This
effectively "re-roots" the entire search under given locations.
Paths which are descendants of the ``CMAKE_STAGING_PREFIX`` are excluded
from this re-rooting, because that variable is always a path on the host system.
By default the ``CMAKE_FIND_ROOT_PATH`` is empty.

The ``CMAKE_SYSROOT`` variable can also be used to specify exactly one
directory to use as a prefix.  Setting ``CMAKE_SYSROOT`` also has other
effects.  See the documentation for that variable for more.

These variables are especially useful when cross-compiling to
point to the root directory of the target environment and CMake will
search there too.  By default at first the directories listed in
``CMAKE_FIND_ROOT_PATH`` are searched, then the ``CMAKE_SYSROOT``
directory is searched, and then the non-rooted directories will be
searched.  The default behavior can be adjusted by setting
``CMAKE_FIND_ROOT_PATH_MODE_PACKAGE``.  This behavior can be manually
overridden on a per-call basis.  By using CMAKE_FIND_ROOT_PATH_BOTH
the search order will be as described above.  If
NO_CMAKE_FIND_ROOT_PATH is used then ``CMAKE_FIND_ROOT_PATH`` will not be
used.  If ONLY_CMAKE_FIND_ROOT_PATH is used then only the re-rooted
directories and directories below ``CMAKE_STAGING_PREFIX`` will be searched.

The default search order is designed to be most-specific to
least-specific for common use cases.
Projects may override the order by simply calling the command
multiple times and using the ``NO_*`` options:

 find_package (<package> PATHS paths... NO_DEFAULT_PATH)
 find_package (<package>)

Once one of the calls succeeds the result variable will be set
and stored in the cache so that no call will search again.

Every non-REQUIRED ``find_package`` call can be disabled by setting the
``CMAKE_DISABLE_FIND_PACKAGE_<PackageName>`` variable to ``TRUE``.

When loading a find module or package configuration file ``find_package``
defines variables to provide information about the call arguments (and
restores their original state before returning):

``<package>_FIND_REQUIRED``
  true if ``REQUIRED`` option was given
``<package>_FIND_QUIETLY``
  true if ``QUIET`` option was given
``<package>_FIND_VERSION``
  full requested version string
``<package>_FIND_VERSION_MAJOR``
  major version if requested, else 0
``<package>_FIND_VERSION_MINOR``
  minor version if requested, else 0
``<package>_FIND_VERSION_PATCH``
  patch version if requested, else 0
``<package>_FIND_VERSION_TWEAK``
  tweak version if requested, else 0
``<package>_FIND_VERSION_COUNT``
  number of version components, 0 to 4
``<package>_FIND_VERSION_EXACT``
  true if ``EXACT`` option was given
``<package>_FIND_COMPONENTS``
  list of requested components
``<package>_FIND_REQUIRED_<c>``
  true if component ``<c>`` is required,
  false if component ``<c>`` is optional

In Module mode the loaded find module is responsible to honor the
request detailed by these variables; see the find module for details.
In Config mode ``find_package`` handles ``REQUIRED``, ``QUIET``, and
``[version]`` options automatically but leaves it to the package
configuration file to handle components in a way that makes sense
for the package.  The package configuration file may set
``<package>_FOUND`` to false to tell ``find_package`` that component
requirements are not satisfied.

See the ``cmake_policy()`` command documentation for discussion
of the ``NO_POLICY_SCOPE`` option.

find_path
---------

A short-hand signature is:

 find_path (<VAR> name1 [path1 path2 ...])

The general signature is:

 find_path (
           <VAR>
           name | NAMES name1 [name2 ...]
           [HINTS path1 [path2 ... ENV var]]
           [PATHS path1 [path2 ... ENV var]]
           [PATH_SUFFIXES suffix1 [suffix2 ...]]
           [DOC "cache documentation string"]
           [NO_DEFAULT_PATH]
           [NO_CMAKE_ENVIRONMENT_PATH]
           [NO_CMAKE_PATH]
           [NO_SYSTEM_ENVIRONMENT_PATH]
           [NO_CMAKE_SYSTEM_PATH]
           [CMAKE_FIND_ROOT_PATH_BOTH |
            ONLY_CMAKE_FIND_ROOT_PATH |
            NO_CMAKE_FIND_ROOT_PATH]
          )

This command is used to find a directory containing the named file.
A cache entry named by ``<VAR>`` is created to store the result
of this command.
If the file in a directory is found the result is stored in the variable
and the search will not be repeated unless the variable is cleared.
If nothing is found, the result will be
``<VAR>-NOTFOUND``, and the search will be attempted again the
next time find_path is invoked with the same variable.
The name of the file in a directory that
is searched for is specified by the names listed
after the NAMES argument.   Additional search locations
can be specified after the PATHS argument.  If ENV var is
found in the HINTS or PATHS section the environment variable var
will be read and converted from a system environment variable to
a cmake style list of paths.  For example ENV PATH would be a way
to list the system path variable. The argument
after DOC will be used for the documentation string in
the cache.
PATH_SUFFIXES specifies additional subdirectories to check below
each search path.

If NO_DEFAULT_PATH is specified, then no additional paths are
added to the search.
If NO_DEFAULT_PATH is not specified, the search process is as follows:

1. Search paths specified in cmake-specific cache variables.
   These are intended to be used on the command line with a -DVAR=value.
   This can be skipped if NO_CMAKE_PATH is passed.

   * <prefix>/include/<arch> if CMAKE_LIBRARY_ARCHITECTURE is set, and <prefix>/include for each <prefix> in CMAKE_PREFIX_PATH
   * CMAKE_INCLUDE_PATH
   * CMAKE_FRAMEWORK_PATH

2. Search paths specified in cmake-specific environment variables.
   These are intended to be set in the user's shell configuration.
   This can be skipped if NO_CMAKE_ENVIRONMENT_PATH is passed.

   * <prefix>/include/<arch> if CMAKE_LIBRARY_ARCHITECTURE is set, and <prefix>/include for each <prefix> in CMAKE_PREFIX_PATH
   * CMAKE_INCLUDE_PATH
   * CMAKE_FRAMEWORK_PATH

3. Search the paths specified by the HINTS option.
   These should be paths computed by system introspection, such as a
   hint provided by the location of another item already found.
   Hard-coded guesses should be specified with the PATHS option.

4. Search the standard system environment variables.
   This can be skipped if NO_SYSTEM_ENVIRONMENT_PATH is an argument.

   * PATH and INCLUDE

5. Search cmake variables defined in the Platform files
   for the current system.  This can be skipped if NO_CMAKE_SYSTEM_PATH
   is passed.

   * <prefix>/include/<arch> if CMAKE_LIBRARY_ARCHITECTURE is set, and <prefix>/include for each <prefix> in CMAKE_SYSTEM_PREFIX_PATH
   * CMAKE_SYSTEM_INCLUDE_PATH
   * CMAKE_SYSTEM_FRAMEWORK_PATH

6. Search the paths specified by the PATHS option
   or in the short-hand version of the command.
   These are typically hard-coded guesses.

On Darwin or systems supporting OS X Frameworks, the cmake variable
CMAKE_FIND_FRAMEWORK can be set to empty or one of the following:

* FIRST: Try to find frameworks before standard libraries or headers.
  This is the default on Darwin.

* LAST: Try to find frameworks after standard libraries or headers.

* ONLY: Only try to find frameworks.

* NEVER: Never try to find frameworks.

On Darwin or systems supporting OS X Application Bundles, the cmake
variable CMAKE_FIND_APPBUNDLE can be set to empty or one of the
following:

* FIRST: Try to find application bundles before standard programs.
  This is the default on Darwin.

* LAST: Try to find application bundles after standard programs.

* ONLY: Only try to find application bundles.

* NEVER: Never try to find application bundles.

The CMake variable ``CMAKE_FIND_ROOT_PATH`` specifies one or more
directories to be prepended to all other search directories.  This
effectively "re-roots" the entire search under given locations.
Paths which are descendants of the ``CMAKE_STAGING_PREFIX`` are excluded
from this re-rooting, because that variable is always a path on the host system.
By default the ``CMAKE_FIND_ROOT_PATH`` is empty.

The ``CMAKE_SYSROOT`` variable can also be used to specify exactly one
directory to use as a prefix.  Setting ``CMAKE_SYSROOT`` also has other
effects.  See the documentation for that variable for more.

These variables are especially useful when cross-compiling to
point to the root directory of the target environment and CMake will
search there too.  By default at first the directories listed in
``CMAKE_FIND_ROOT_PATH`` are searched, then the ``CMAKE_SYSROOT``
directory is searched, and then the non-rooted directories will be
searched.  The default behavior can be adjusted by setting
``CMAKE_FIND_ROOT_PATH_MODE_INCLUDE``.  This behavior can be manually
overridden on a per-call basis.  By using CMAKE_FIND_ROOT_PATH_BOTH
the search order will be as described above.  If
NO_CMAKE_FIND_ROOT_PATH is used then ``CMAKE_FIND_ROOT_PATH`` will not be
used.  If ONLY_CMAKE_FIND_ROOT_PATH is used then only the re-rooted
directories and directories below ``CMAKE_STAGING_PREFIX`` will be searched.

The default search order is designed to be most-specific to
least-specific for common use cases.
Projects may override the order by simply calling the command
multiple times and using the ``NO_*`` options:

 find_path (<VAR> NAMES name PATHS paths... NO_DEFAULT_PATH)
 find_path (<VAR> NAMES name)

Once one of the calls succeeds the result variable will be set
and stored in the cache so that no call will search again.

When searching for frameworks, if the file is specified as A/b.h, then
the framework search will look for A.framework/Headers/b.h.  If that
is found the path will be set to the path to the framework.  CMake
will convert this to the correct -F option to include the file.

find_program
------------

A short-hand signature is:

 find_program (<VAR> name1 [path1 path2 ...])

The general signature is:

 find_program (
           <VAR>
           name | NAMES name1 [name2 ...]
           [HINTS path1 [path2 ... ENV var]]
           [PATHS path1 [path2 ... ENV var]]
           [PATH_SUFFIXES suffix1 [suffix2 ...]]
           [DOC "cache documentation string"]
           [NO_DEFAULT_PATH]
           [NO_CMAKE_ENVIRONMENT_PATH]
           [NO_CMAKE_PATH]
           [NO_SYSTEM_ENVIRONMENT_PATH]
           [NO_CMAKE_SYSTEM_PATH]
           [CMAKE_FIND_ROOT_PATH_BOTH |
            ONLY_CMAKE_FIND_ROOT_PATH |
            NO_CMAKE_FIND_ROOT_PATH]
          )

This command is used to find a program.
A cache entry named by ``<VAR>`` is created to store the result
of this command.
If the program is found the result is stored in the variable
and the search will not be repeated unless the variable is cleared.
If nothing is found, the result will be
``<VAR>-NOTFOUND``, and the search will be attempted again the
next time find_program is invoked with the same variable.
The name of the program that
is searched for is specified by the names listed
after the NAMES argument.   Additional search locations
can be specified after the PATHS argument.  If ENV var is
found in the HINTS or PATHS section the environment variable var
will be read and converted from a system environment variable to
a cmake style list of paths.  For example ENV PATH would be a way
to list the system path variable. The argument
after DOC will be used for the documentation string in
the cache.
PATH_SUFFIXES specifies additional subdirectories to check below
each search path.

If NO_DEFAULT_PATH is specified, then no additional paths are
added to the search.
If NO_DEFAULT_PATH is not specified, the search process is as follows:

1. Search paths specified in cmake-specific cache variables.
   These are intended to be used on the command line with a -DVAR=value.
   This can be skipped if NO_CMAKE_PATH is passed.

   * <prefix>/[s]bin for each <prefix> in CMAKE_PREFIX_PATH
   * CMAKE_PROGRAM_PATH
   * CMAKE_APPBUNDLE_PATH

2. Search paths specified in cmake-specific environment variables.
   These are intended to be set in the user's shell configuration.
   This can be skipped if NO_CMAKE_ENVIRONMENT_PATH is passed.

   * <prefix>/[s]bin for each <prefix> in CMAKE_PREFIX_PATH
   * CMAKE_PROGRAM_PATH
   * CMAKE_APPBUNDLE_PATH

3. Search the paths specified by the HINTS option.
   These should be paths computed by system introspection, such as a
   hint provided by the location of another item already found.
   Hard-coded guesses should be specified with the PATHS option.

4. Search the standard system environment variables.
   This can be skipped if NO_SYSTEM_ENVIRONMENT_PATH is an argument.

   * PATH

5. Search cmake variables defined in the Platform files
   for the current system.  This can be skipped if NO_CMAKE_SYSTEM_PATH
   is passed.

   * <prefix>/[s]bin for each <prefix> in CMAKE_SYSTEM_PREFIX_PATH
   * CMAKE_SYSTEM_PROGRAM_PATH
   * CMAKE_SYSTEM_APPBUNDLE_PATH

6. Search the paths specified by the PATHS option
   or in the short-hand version of the command.
   These are typically hard-coded guesses.

On Darwin or systems supporting OS X Frameworks, the cmake variable
CMAKE_FIND_FRAMEWORK can be set to empty or one of the following:

* FIRST: Try to find frameworks before standard libraries or headers.
  This is the default on Darwin.

* LAST: Try to find frameworks after standard libraries or headers.

* ONLY: Only try to find frameworks.

* NEVER: Never try to find frameworks.

On Darwin or systems supporting OS X Application Bundles, the cmake
variable CMAKE_FIND_APPBUNDLE can be set to empty or one of the
following:

* FIRST: Try to find application bundles before standard programs.
  This is the default on Darwin.

* LAST: Try to find application bundles after standard programs.

* ONLY: Only try to find application bundles.

* NEVER: Never try to find application bundles.

The CMake variable ``CMAKE_FIND_ROOT_PATH`` specifies one or more
directories to be prepended to all other search directories.  This
effectively "re-roots" the entire search under given locations.
Paths which are descendants of the ``CMAKE_STAGING_PREFIX`` are excluded
from this re-rooting, because that variable is always a path on the host system.
By default the ``CMAKE_FIND_ROOT_PATH`` is empty.

The ``CMAKE_SYSROOT`` variable can also be used to specify exactly one
directory to use as a prefix.  Setting ``CMAKE_SYSROOT`` also has other
effects.  See the documentation for that variable for more.

These variables are especially useful when cross-compiling to
point to the root directory of the target environment and CMake will
search there too.  By default at first the directories listed in
``CMAKE_FIND_ROOT_PATH`` are searched, then the ``CMAKE_SYSROOT``
directory is searched, and then the non-rooted directories will be
searched.  The default behavior can be adjusted by setting
``CMAKE_FIND_ROOT_PATH_MODE_PROGRAM``.  This behavior can be manually
overridden on a per-call basis.  By using CMAKE_FIND_ROOT_PATH_BOTH
the search order will be as described above.  If
NO_CMAKE_FIND_ROOT_PATH is used then ``CMAKE_FIND_ROOT_PATH`` will not be
used.  If ONLY_CMAKE_FIND_ROOT_PATH is used then only the re-rooted
directories and directories below ``CMAKE_STAGING_PREFIX`` will be searched.

The default search order is designed to be most-specific to
least-specific for common use cases.
Projects may override the order by simply calling the command
multiple times and using the ``NO_*`` options:

 find_program (<VAR> NAMES name PATHS paths... NO_DEFAULT_PATH)
 find_program (<VAR> NAMES name)

Once one of the calls succeeds the result variable will be set
and stored in the cache so that no call will search again.

fltk_wrap_ui
------------

Create FLTK user interfaces Wrappers.

::

 fltk_wrap_ui(resultingLibraryName source1
              source2 ... sourceN )

Produce .h and .cxx files for all the .fl and .fld files listed.  The
resulting .h and .cxx files will be added to a variable named
resultingLibraryName_FLTK_UI_SRCS which should be added to your
library.

foreach
-------

Evaluate a group of commands for each value in a list.

::

 foreach(loop_var arg1 arg2 ...)
   COMMAND1(ARGS ...)
   COMMAND2(ARGS ...)
   ...
 endforeach(loop_var)

All commands between foreach and the matching endforeach are recorded
without being invoked.  Once the endforeach is evaluated, the recorded
list of commands is invoked once for each argument listed in the
original foreach command.  Before each iteration of the loop
"${loop_var}" will be set as a variable with the current value in the
list.

::

 foreach(loop_var RANGE total)
 foreach(loop_var RANGE start stop [step])

Foreach can also iterate over a generated range of numbers.  There are
three types of this iteration:

* When specifying single number, the range will have elements 0 to
  "total".

* When specifying two numbers, the range will have elements from the
  first number to the second number.

* The third optional number is the increment used to iterate from the
  first number to the second number.

::

 foreach(loop_var IN [LISTS [list1 [...]]]
                     [ITEMS [item1 [...]]])

Iterates over a precise list of items.  The LISTS option names
list-valued variables to be traversed, including empty elements (an
empty string is a zero-length list).  (Note macro
arguments are not variables.)  The ITEMS option ends argument
parsing and includes all arguments following it in the iteration.

function
--------

Start recording a function for later invocation as a command.

::

 function(<name> [arg1 [arg2 [arg3 ...]]])
   COMMAND1(ARGS ...)
   COMMAND2(ARGS ...)
   ...
 endfunction(<name>)

Define a function named <name> that takes arguments named arg1 arg2
arg3 (...).  Commands listed after function, but before the matching
endfunction, are not invoked until the function is invoked.  When it
is invoked, the commands recorded in the function are first modified
by replacing formal parameters (${arg1}) with the arguments passed,
and then invoked as normal commands.  In addition to referencing the
formal parameters you can reference the variable ARGC which will be
set to the number of arguments passed into the function as well as
ARGV0 ARGV1 ARGV2 ...  which will have the actual values of the
arguments passed in.  This facilitates creating functions with
optional arguments.  Additionally ARGV holds the list of all arguments
given to the function and ARGN holds the list of arguments past the
last expected argument.

A function opens a new scope: see set(var PARENT_SCOPE) for details.

See the cmake_policy() command documentation for the behavior of
policies inside functions.

get_cmake_property
------------------

Get a property of the CMake instance.

::

 get_cmake_property(VAR property)

Get a property from the CMake instance.  The value of the property is
stored in the variable VAR.  If the property is not found, VAR will be
set to "NOTFOUND".  Some supported properties include: VARIABLES,
CACHE_VARIABLES, COMMANDS, MACROS, and COMPONENTS.

See also the more general get_property() command.

get_directory_property
----------------------

Get a property of DIRECTORY scope.

::

 get_directory_property(<variable> [DIRECTORY <dir>] <prop-name>)

Store a property of directory scope in the named variable.  If the
property is not defined the empty-string is returned.  The DIRECTORY
argument specifies another directory from which to retrieve the
property value.  The specified directory must have already been
traversed by CMake.

::

 get_directory_property(<variable> [DIRECTORY <dir>]
                        DEFINITION <var-name>)

Get a variable definition from a directory.  This form is useful to
get a variable definition from another directory.

See also the more general get_property() command.

get_filename_component
----------------------

Get a specific component of a full filename.

::

 get_filename_component(<VAR> <FileName> <COMP> [CACHE])

Set <VAR> to a component of <FileName>, where <COMP> is one of:

::

 DIRECTORY = Directory without file name
 NAME      = File name without directory
 EXT       = File name longest extension (.b.c from d/a.b.c)
 NAME_WE   = File name without directory or longest extension
 ABSOLUTE  = Full path to file
 REALPATH  = Full path to existing file with symlinks resolved
 PATH      = Legacy alias for DIRECTORY (use for CMake <= 2.8.11)

Paths are returned with forward slashes and have no trailing slahes.
The longest file extension is always considered.  If the optional
CACHE argument is specified, the result variable is added to the
cache.

::

 get_filename_component(<VAR> FileName
                        PROGRAM [PROGRAM_ARGS <ARG_VAR>]
                        [CACHE])

The program in FileName will be found in the system search path or
left as a full path.  If PROGRAM_ARGS is present with PROGRAM, then
any command-line arguments present in the FileName string are split
from the program name and stored in <ARG_VAR>.  This is used to
separate a program name from its arguments in a command line string.

get_property
------------

Get a property.

::

 get_property(<variable>
              <GLOBAL             |
               DIRECTORY [dir]    |
               TARGET    <target> |
               SOURCE    <source> |
               TEST      <test>   |
               CACHE     <entry>  |
               VARIABLE>
              PROPERTY <name>
              [SET | DEFINED | BRIEF_DOCS | FULL_DOCS])

Get one property from one object in a scope.  The first argument
specifies the variable in which to store the result.  The second
argument determines the scope from which to get the property.  It must
be one of the following:

GLOBAL scope is unique and does not accept a name.

DIRECTORY scope defaults to the current directory but another
directory (already processed by CMake) may be named by full or
relative path.

TARGET scope must name one existing target.

SOURCE scope must name one source file.

TEST scope must name one existing test.

CACHE scope must name one cache entry.

VARIABLE scope is unique and does not accept a name.

The required PROPERTY option is immediately followed by the name of
the property to get.  If the property is not set an empty value is
returned.  If the SET option is given the variable is set to a boolean
value indicating whether the property has been set.  If the DEFINED
option is given the variable is set to a boolean value indicating
whether the property has been defined such as with define_property.
If BRIEF_DOCS or FULL_DOCS is given then the variable is set to a
string containing documentation for the requested property.  If
documentation is requested for a property that has not been defined
NOTFOUND is returned.

get_source_file_property
------------------------

Get a property for a source file.

::

 get_source_file_property(VAR file property)

Get a property from a source file.  The value of the property is
stored in the variable VAR.  If the property is not found, VAR will be
set to "NOTFOUND".  Use set_source_files_properties to set property
values.  Source file properties usually control how the file is built.
One property that is always there is LOCATION

See also the more general get_property() command.

get_target_property
-------------------

Get a property from a target.

::

 get_target_property(VAR target property)

Get a property from a target.  The value of the property is stored in
the variable VAR.  If the property is not found, VAR will be set to
"NOTFOUND".  Use set_target_properties to set property values.
Properties are usually used to control how a target is built, but some
query the target instead.  This command can get properties for any
target so far created.  The targets do not need to be in the current
CMakeLists.txt file.

See also the more general get_property() command.

get_test_property
-----------------

Get a property of the test.

::

 get_test_property(test property VAR)

Get a property from the Test.  The value of the property is stored in
the variable VAR.  If the property is not found, VAR will be set to
"NOTFOUND".  For a list of standard properties you can type cmake
--help-property-list

See also the more general get_property() command.

if
--

Conditionally execute a group of commands.

 if(expression)
   # then section.
   COMMAND1(ARGS ...)
   COMMAND2(ARGS ...)
   ...
 elseif(expression2)
   # elseif section.
   COMMAND1(ARGS ...)
   COMMAND2(ARGS ...)
   ...
 else(expression)
   # else section.
   COMMAND1(ARGS ...)
   COMMAND2(ARGS ...)
   ...
 endif(expression)

Evaluates the given expression.  If the result is true, the commands
in the THEN section are invoked.  Otherwise, the commands in the else
section are invoked.  The elseif and else sections are optional.  You
may have multiple elseif clauses.  Note that the expression in the
else and endif clause is optional.  Long expressions can be used and
there is a traditional order of precedence.  Parenthetical expressions
are evaluated first followed by unary tests such as ``EXISTS``,
``COMMAND``, and ``DEFINED``.  Then any binary tests such as
``EQUAL``, ``LESS``, ``GREATER``, ``STRLESS``, ``STRGREATER``,
``STREQUAL``, and ``MATCHES`` will be evaluated.  Then boolean ``NOT``
operators and finally boolean ``AND`` and then ``OR`` operators will
be evaluated.

Possible expressions are:

``if(<constant>)``
 True if the constant is ``1``, ``ON``, ``YES``, ``TRUE``, ``Y``,
 or a non-zero number.  False if the constant is ``0``, ``OFF``,
 ``NO``, ``FALSE``, ``N``, ``IGNORE``, ``NOTFOUND``, the empty string,
 or ends in the suffix ``-NOTFOUND``.  Named boolean constants are
 case-insensitive.  If the argument is not one of these constants, it
 is treated as a variable.

``if(<variable>)``
 True if the variable is defined to a value that is not a false
 constant.  False otherwise.  (Note macro arguments are not variables.)

``if(NOT <expression>)``
 True if the expression is not true.

``if(<expr1> AND <expr2>)``
 True if both expressions would be considered true individually.

``if(<expr1> OR <expr2>)``
 True if either expression would be considered true individually.

``if(COMMAND command-name)``
 True if the given name is a command, macro or function that can be
 invoked.

``if(POLICY policy-id)``
 True if the given name is an existing policy (of the form ``CMP<NNNN>``).

``if(TARGET target-name)``
 True if the given name is an existing logical target name such as those
 created by the ``add_executable()``, ``add_library()``, or
 ``add_custom_target()`` commands.

``if(EXISTS path-to-file-or-directory)``
 True if the named file or directory exists.  Behavior is well-defined
 only for full paths.

``if(file1 IS_NEWER_THAN file2)``
 True if file1 is newer than file2 or if one of the two files doesn't
 exist.  Behavior is well-defined only for full paths.  If the file
 time stamps are exactly the same, an ``IS_NEWER_THAN`` comparison returns
 true, so that any dependent build operations will occur in the event
 of a tie.  This includes the case of passing the same file name for
 both file1 and file2.

``if(IS_DIRECTORY path-to-directory)``
 True if the given name is a directory.  Behavior is well-defined only
 for full paths.

``if(IS_SYMLINK file-name)``
 True if the given name is a symbolic link.  Behavior is well-defined
 only for full paths.

``if(IS_ABSOLUTE path)``
 True if the given path is an absolute path.

``if(<variable|string> MATCHES regex)``
 True if the given string or variable's value matches the given regular
 expression.

``if(<variable|string> LESS <variable|string>)``
 True if the given string or variable's value is a valid number and less
 than that on the right.

``if(<variable|string> GREATER <variable|string>)``
 True if the given string or variable's value is a valid number and greater
 than that on the right.

``if(<variable|string> EQUAL <variable|string>)``
 True if the given string or variable's value is a valid number and equal
 to that on the right.

``if(<variable|string> STRLESS <variable|string>)``
 True if the given string or variable's value is lexicographically less
 than the string or variable on the right.

``if(<variable|string> STRGREATER <variable|string>)``
 True if the given string or variable's value is lexicographically greater
 than the string or variable on the right.

``if(<variable|string> STREQUAL <variable|string>)``
 True if the given string or variable's value is lexicographically equal
 to the string or variable on the right.

``if(<variable|string> VERSION_LESS <variable|string>)``
 Component-wise integer version number comparison (version format is
 ``major[.minor[.patch[.tweak]]]``).

``if(<variable|string> VERSION_EQUAL <variable|string>)``
 Component-wise integer version number comparison (version format is
 ``major[.minor[.patch[.tweak]]]``).

``if(<variable|string> VERSION_GREATER <variable|string>)``
 Component-wise integer version number comparison (version format is
 ``major[.minor[.patch[.tweak]]]``).

``if(DEFINED <variable>)``
 True if the given variable is defined.  It does not matter if the
 variable is true or false just if it has been set.  (Note macro
 arguments are not variables.)

``if((expression) AND (expression OR (expression)))``
 The expressions inside the parenthesis are evaluated first and then
 the remaining expression is evaluated as in the previous examples.
 Where there are nested parenthesis the innermost are evaluated as part
 of evaluating the expression that contains them.

The if command was written very early in CMake's history, predating
the ``${}`` variable evaluation syntax, and for convenience evaluates
variables named by its arguments as shown in the above signatures.
Note that normal variable evaluation with ``${}`` applies before the if
command even receives the arguments.  Therefore code like::

 set(var1 OFF)
 set(var2 "var1")
 if(${var2})

appears to the if command as::

 if(var1)

and is evaluated according to the ``if(<variable>)`` case documented
above.  The result is ``OFF`` which is false.  However, if we remove the
``${}`` from the example then the command sees::

 if(var2)

which is true because ``var2`` is defined to "var1" which is not a false
constant.

Automatic evaluation applies in the other cases whenever the
above-documented signature accepts ``<variable|string>``:

* The left hand argument to ``MATCHES`` is first checked to see if it is
  a defined variable, if so the variable's value is used, otherwise the
  original value is used.

* If the left hand argument to ``MATCHES`` is missing it returns false
  without error

* Both left and right hand arguments to ``LESS``, ``GREATER``, and
  ``EQUAL`` are independently tested to see if they are defined
  variables, if so their defined values are used otherwise the original
  value is used.

* Both left and right hand arguments to ``STRLESS``, ``STREQUAL``, and
  ``STRGREATER`` are independently tested to see if they are defined
  variables, if so their defined values are used otherwise the original
  value is used.

* Both left and right hand arguments to ``VERSION_LESS``,
  ``VERSION_EQUAL``, and ``VERSION_GREATER`` are independently tested
  to see if they are defined variables, if so their defined values are
  used otherwise the original value is used.

* The right hand argument to ``NOT`` is tested to see if it is a boolean
  constant, if so the value is used, otherwise it is assumed to be a
  variable and it is dereferenced.

* The left and right hand arguments to ``AND`` and ``OR`` are independently
  tested to see if they are boolean constants, if so they are used as
  such, otherwise they are assumed to be variables and are dereferenced.

include_directories
-------------------

Add include directories to the build.

::

 include_directories([AFTER|BEFORE] [SYSTEM] dir1 [dir2 ...])

Add the given directories to those the compiler uses to search for
include files.  Relative paths are interpreted as relative to the
current source directory.

The include directories are added to the ``INCLUDE_DIRECTORIES``
directory property for the current ``CMakeLists`` file.  They are also
added to the ``INCLUDE_DIRECTORIES`` target property for each
target in the current ``CMakeLists`` file.  The target property values
are the ones used by the generators.

By default the directories specified are appended onto the current list of
directories.  This default behavior can be changed by setting
``CMAKE_INCLUDE_DIRECTORIES_BEFORE`` to ``ON``.  By using
``AFTER`` or ``BEFORE`` explicitly, you can select between appending and
prepending, independent of the default.

If the ``SYSTEM`` option is given, the compiler will be told the
directories are meant as system include directories on some platforms.
Signalling this setting might achieve effects such as the compiler
skipping warnings, or these fixed-install system files not being
considered in dependency calculations - see compiler docs.

Arguments to ``include_directories`` may use "generator expressions" with
the syntax "$<...>".  See the ``cmake-generator-expressions(7)``
manual for available expressions.  See the ``cmake-buildsystem(7)``
manual for more on defining buildsystem properties.

include_external_msproject
--------------------------

Include an external Microsoft project file in a workspace.

::

 include_external_msproject(projectname location
                            [TYPE projectTypeGUID]
                            [GUID projectGUID]
                            [PLATFORM platformName]
                            dep1 dep2 ...)

Includes an external Microsoft project in the generated workspace
file.  Currently does nothing on UNIX.  This will create a target
named [projectname].  This can be used in the add_dependencies command
to make things depend on the external project.

TYPE, GUID and PLATFORM are optional parameters that allow one to
specify the type of project, id (GUID) of the project and the name of
the target platform.  This is useful for projects requiring values
other than the default (e.g.  WIX projects).  These options are not
supported by the Visual Studio 6 generator.

include_regular_expression
--------------------------

Set the regular expression used for dependency checking.

::

 include_regular_expression(regex_match [regex_complain])

Set the regular expressions used in dependency checking.  Only files
matching regex_match will be traced as dependencies.  Only files
matching regex_complain will generate warnings if they cannot be found
(standard header paths are not searched).  The defaults are:

::

 regex_match    = "^.*$" (match everything)
 regex_complain = "^$" (match empty string only)

include
-------

Load and run CMake code from a file or module.

::

 include(<file|module> [OPTIONAL] [RESULT_VARIABLE <VAR>]
                       [NO_POLICY_SCOPE])

Load and run CMake code from the file given.  Variable reads and
writes access the scope of the caller (dynamic scoping).  If OPTIONAL
is present, then no error is raised if the file does not exist.  If
RESULT_VARIABLE is given the variable will be set to the full filename
which has been included or NOTFOUND if it failed.

If a module is specified instead of a file, the file with name
<modulename>.cmake is searched first in CMAKE_MODULE_PATH, then in the
CMake module directory.  There is one exception to this: if the file
which calls include() is located itself in the CMake module directory,
then first the CMake module directory is searched and
CMAKE_MODULE_PATH afterwards.  See also policy CMP0017.

See the cmake_policy() command documentation for discussion of the
NO_POLICY_SCOPE option.

install
-------

Specify rules to run at install time.

This command generates installation rules for a project.  Rules
specified by calls to this command within a source directory are
executed in order during installation.  The order across directories
is not defined.

There are multiple signatures for this command.  Some of them define
installation options for files and targets.  Options common to
multiple signatures are covered here but they are valid only for
signatures that specify them.  The common options are:

``DESTINATION``
  Specify the directory on disk to which a file will be installed.
  If a full path (with a leading slash or drive letter) is given
  it is used directly.  If a relative path is given it is interpreted
  relative to the value of the ``CMAKE_INSTALL_PREFIX`` variable.
  The prefix can be relocated at install time using the ``DESTDIR``
  mechanism explained in the ``CMAKE_INSTALL_PREFIX`` variable
  documentation.

``PERMISSIONS``
  Specify permissions for installed files.  Valid permissions are
  ``OWNER_READ``, ``OWNER_WRITE``, ``OWNER_EXECUTE``, ``GROUP_READ``,
  ``GROUP_WRITE``, ``GROUP_EXECUTE``, ``WORLD_READ``, ``WORLD_WRITE``,
  ``WORLD_EXECUTE``, ``SETUID``, and ``SETGID``.  Permissions that do
  not make sense on certain platforms are ignored on those platforms.

``CONFIGURATIONS``
  Specify a list of build configurations for which the install rule
  applies (Debug, Release, etc.).

``COMPONENT``
  Specify an installation component name with which the install rule
  is associated, such as "runtime" or "development".  During
  component-specific installation only install rules associated with
  the given component name will be executed.  During a full installation
  all components are installed.  If ``COMPONENT`` is not provided a
  default component "Unspecified" is created.  The default component
  name may be controlled with the
  ``CMAKE_INSTALL_DEFAULT_COMPONENT_NAME`` variable.

``RENAME``
  Specify a name for an installed file that may be different from the
  original file.  Renaming is allowed only when a single file is
  installed by the command.

``OPTIONAL``
  Specify that it is not an error if the file to be installed does
  not exist.

------------------------------------------------------------------------------

::

 install(TARGETS targets... [EXPORT <export-name>]
         [[ARCHIVE|LIBRARY|RUNTIME|FRAMEWORK|BUNDLE|
           PRIVATE_HEADER|PUBLIC_HEADER|RESOURCE]
          [DESTINATION <dir>]
          [INCLUDES DESTINATION [<dir> ...]]
          [PERMISSIONS permissions...]
          [CONFIGURATIONS [Debug|Release|...]]
          [COMPONENT <component>]
          [OPTIONAL] [NAMELINK_ONLY|NAMELINK_SKIP]
         ] [...])

The ``TARGETS`` form specifies rules for installing targets from a
project.  There are five kinds of target files that may be installed:
``ARCHIVE``, ``LIBRARY``, ``RUNTIME``, ``FRAMEWORK``, and ``BUNDLE``.
Executables are treated as ``RUNTIME`` targets, except that those
marked with the ``MACOSX_BUNDLE`` property are treated as ``BUNDLE``
targets on OS X.  Static libraries are always treated as ``ARCHIVE``
targets.  Module libraries are always treated as ``LIBRARY`` targets.
For non-DLL platforms shared libraries are treated as ``LIBRARY``
targets, except that those marked with the ``FRAMEWORK`` property are
treated as ``FRAMEWORK`` targets on OS X.  For DLL platforms the DLL
part of a shared library is treated as a ``RUNTIME`` target and the
corresponding import library is treated as an ``ARCHIVE`` target.
All Windows-based systems including Cygwin are DLL platforms.
The ``ARCHIVE``, ``LIBRARY``, ``RUNTIME``, and ``FRAMEWORK`` arguments
change the type of target to which the subsequent properties apply.
If none is given the installation properties apply to all target
types.  If only one is given then only targets of that type will be
installed (which can be used to install just a DLL or just an import
library).  The ``INCLUDES DESTINATION`` specifies a list of directories
which will be added to the ``INTERFACE_INCLUDE_DIRECTORIES``
target property of the ``<targets>`` when exported by the
``install(EXPORT)`` command.  If a relative path is
specified, it is treated as relative to the ``$<INSTALL_PREFIX>``.

The ``PRIVATE_HEADER``, ``PUBLIC_HEADER``, and ``RESOURCE`` arguments
cause subsequent properties to be applied to installing a ``FRAMEWORK``
shared library target's associated files on non-Apple platforms.  Rules
defined by these arguments are ignored on Apple platforms because the
associated files are installed into the appropriate locations inside
the framework folder.  See documentation of the
``PRIVATE_HEADER``, ``PUBLIC_HEADER``, and
``RESOURCE`` target properties for details.

Either ``NAMELINK_ONLY`` or ``NAMELINK_SKIP`` may be specified as a
``LIBRARY`` option.  On some platforms a versioned shared library
has a symbolic link such as::

 lib<name>.so -> lib<name>.so.1

where ``lib<name>.so.1`` is the soname of the library and ``lib<name>.so``
is a "namelink" allowing linkers to find the library when given
``-l<name>``.  The ``NAMELINK_ONLY`` option causes installation of only the
namelink when a library target is installed.  The ``NAMELINK_SKIP`` option
causes installation of library files other than the namelink when a
library target is installed.  When neither option is given both
portions are installed.  On platforms where versioned shared libraries
do not have namelinks or when a library is not versioned the
``NAMELINK_SKIP`` option installs the library and the ``NAMELINK_ONLY``
option installs nothing.  See the ``VERSION`` and
``SOVERSION`` target properties for details on creating versioned
shared libraries.

One or more groups of properties may be specified in a single call to
the ``TARGETS`` form of this command.  A target may be installed more than
once to different locations.  Consider hypothetical targets ``myExe``,
``mySharedLib``, and ``myStaticLib``.  The code:

 install(TARGETS myExe mySharedLib myStaticLib
         RUNTIME DESTINATION bin
         LIBRARY DESTINATION lib
         ARCHIVE DESTINATION lib/static)
 install(TARGETS mySharedLib DESTINATION /some/full/path)

will install ``myExe`` to ``<prefix>/bin`` and ``myStaticLib`` to
``<prefix>/lib/static``.  On non-DLL platforms ``mySharedLib`` will be
installed to ``<prefix>/lib`` and ``/some/full/path``.  On DLL platforms
the ``mySharedLib`` DLL will be installed to ``<prefix>/bin`` and
``/some/full/path`` and its import library will be installed to
``<prefix>/lib/static`` and ``/some/full/path``.

The ``EXPORT`` option associates the installed target files with an
export called ``<export-name>``.  It must appear before any ``RUNTIME``,
``LIBRARY``, or ``ARCHIVE`` options.  To actually install the export
file itself, call ``install(EXPORT)``, documented below.

Installing a target with the ``EXCLUDE_FROM_ALL`` target property
set to ``TRUE`` has undefined behavior.

------------------------------------------------------------------------------

::

 install(<FILES|PROGRAMS> files... DESTINATION <dir>
         [PERMISSIONS permissions...]
         [CONFIGURATIONS [Debug|Release|...]]
         [COMPONENT <component>]
         [RENAME <name>] [OPTIONAL])

The ``FILES`` form specifies rules for installing files for a project.
File names given as relative paths are interpreted with respect to the
current source directory.  Files installed by this form are by default
given permissions ``OWNER_WRITE``, ``OWNER_READ``, ``GROUP_READ``, and
``WORLD_READ`` if no ``PERMISSIONS`` argument is given.

The ``PROGRAMS`` form is identical to the ``FILES`` form except that the
default permissions for the installed file also include ``OWNER_EXECUTE``,
``GROUP_EXECUTE``, and ``WORLD_EXECUTE``.  This form is intended to install
programs that are not targets, such as shell scripts.  Use the ``TARGETS``
form to install targets built within the project.

The list of ``files...`` given to ``FILES`` or ``PROGRAMS`` may use
"generator expressions" with the syntax ``$<...>``.  See the
``cmake-generator-expressions(7)`` manual for available expressions.
However, if any item begins in a generator expression it must evaluate
to a full path.

------------------------------------------------------------------------------

::

 install(DIRECTORY dirs... DESTINATION <dir>
         [FILE_PERMISSIONS permissions...]
         [DIRECTORY_PERMISSIONS permissions...]
         [USE_SOURCE_PERMISSIONS] [OPTIONAL]
         [CONFIGURATIONS [Debug|Release|...]]
         [COMPONENT <component>] [FILES_MATCHING]
         [[PATTERN <pattern> | REGEX <regex>]
          [EXCLUDE] [PERMISSIONS permissions...]] [...])

The ``DIRECTORY`` form installs contents of one or more directories to a
given destination.  The directory structure is copied verbatim to the
destination.  The last component of each directory name is appended to
the destination directory but a trailing slash may be used to avoid
this because it leaves the last component empty.  Directory names
given as relative paths are interpreted with respect to the current
source directory.  If no input directory names are given the
destination directory will be created but nothing will be installed
into it.  The ``FILE_PERMISSIONS`` and ``DIRECTORY_PERMISSIONS`` options
specify permissions given to files and directories in the destination.
If ``USE_SOURCE_PERMISSIONS`` is specified and ``FILE_PERMISSIONS`` is not,
file permissions will be copied from the source directory structure.
If no permissions are specified files will be given the default
permissions specified in the ``FILES`` form of the command, and the
directories will be given the default permissions specified in the
``PROGRAMS`` form of the command.

Installation of directories may be controlled with fine granularity
using the ``PATTERN`` or ``REGEX`` options.  These "match" options specify a
globbing pattern or regular expression to match directories or files
encountered within input directories.  They may be used to apply
certain options (see below) to a subset of the files and directories
encountered.  The full path to each input file or directory (with
forward slashes) is matched against the expression.  A ``PATTERN`` will
match only complete file names: the portion of the full path matching
the pattern must occur at the end of the file name and be preceded by
a slash.  A ``REGEX`` will match any portion of the full path but it may
use ``/`` and ``$`` to simulate the ``PATTERN`` behavior.  By default all
files and directories are installed whether or not they are matched.
The ``FILES_MATCHING`` option may be given before the first match option
to disable installation of files (but not directories) not matched by
any expression.  For example, the code

 install(DIRECTORY src/ DESTINATION include/myproj
         FILES_MATCHING PATTERN "*.h")

will extract and install header files from a source tree.

Some options may follow a ``PATTERN`` or ``REGEX`` expression and are applied
only to files or directories matching them.  The ``EXCLUDE`` option will
skip the matched file or directory.  The ``PERMISSIONS`` option overrides
the permissions setting for the matched file or directory.  For
example the code

 install(DIRECTORY icons scripts/ DESTINATION share/myproj
         PATTERN "CVS" EXCLUDE
         PATTERN "scripts/*"
         PERMISSIONS OWNER_EXECUTE OWNER_WRITE OWNER_READ
                     GROUP_EXECUTE GROUP_READ)

will install the ``icons`` directory to ``share/myproj/icons`` and the
``scripts`` directory to ``share/myproj``.  The icons will get default
file permissions, the scripts will be given specific permissions, and any
``CVS`` directories will be excluded.

------------------------------------------------------------------------------

::

 install([[SCRIPT <file>] [CODE <code>]] [...])

The ``SCRIPT`` form will invoke the given CMake script files during
installation.  If the script file name is a relative path it will be
interpreted with respect to the current source directory.  The ``CODE``
form will invoke the given CMake code during installation.  Code is
specified as a single argument inside a double-quoted string.  For
example, the code

 install(CODE "MESSAGE(\"Sample install message.\")")

will print a message during installation.

------------------------------------------------------------------------------

::

 install(EXPORT <export-name> DESTINATION <dir>
         [NAMESPACE <namespace>] [FILE <name>.cmake]
         [PERMISSIONS permissions...]
         [CONFIGURATIONS [Debug|Release|...]]
         [EXPORT_LINK_INTERFACE_LIBRARIES]
         [COMPONENT <component>])

The ``EXPORT`` form generates and installs a CMake file containing code to
import targets from the installation tree into another project.
Target installations are associated with the export ``<export-name>``
using the ``EXPORT`` option of the ``install(TARGETS)`` signature
documented above.  The ``NAMESPACE`` option will prepend ``<namespace>`` to
the target names as they are written to the import file.  By default
the generated file will be called ``<export-name>.cmake`` but the ``FILE``
option may be used to specify a different name.  The value given to
the ``FILE`` option must be a file name with the ``.cmake`` extension.
If a ``CONFIGURATIONS`` option is given then the file will only be installed
when one of the named configurations is installed.  Additionally, the
generated import file will reference only the matching target
configurations.  The ``EXPORT_LINK_INTERFACE_LIBRARIES`` keyword, if
present, causes the contents of the properties matching
``(IMPORTED_)?LINK_INTERFACE_LIBRARIES(_<CONFIG>)?`` to be exported, when
policy ``CMP0022`` is ``NEW``.  If a ``COMPONENT`` option is
specified that does not match that given to the targets associated with
``<export-name>`` the behavior is undefined.  If a library target is
included in the export but a target to which it links is not included
the behavior is unspecified.

The ``EXPORT`` form is useful to help outside projects use targets built
and installed by the current project.  For example, the code

 install(TARGETS myexe EXPORT myproj DESTINATION bin)
 install(EXPORT myproj NAMESPACE mp_ DESTINATION lib/myproj)

will install the executable myexe to ``<prefix>/bin`` and code to import
it in the file ``<prefix>/lib/myproj/myproj.cmake``.  An outside project
may load this file with the include command and reference the ``myexe``
executable from the installation tree using the imported target name
``mp_myexe`` as if the target were built in its own tree.

.. note::
  This command supercedes the ``install_targets()`` command and
  the ``PRE_INSTALL_SCRIPT`` and ``POST_INSTALL_SCRIPT``
  target properties.  It also replaces the ``FILES`` forms of the
  ``install_files()`` and ``install_programs()`` commands.
  The processing order of these install rules relative to
  those generated by ``install_targets()``,
  ``install_files()``, and ``install_programs()`` commands
  is not defined.

link_directories
----------------

Specify directories in which the linker will look for libraries.

::

 link_directories(directory1 directory2 ...)

Specify the paths in which the linker should search for libraries.
The command will apply only to targets created after it is called.
Relative paths given to this command are interpreted as relative to
the current source directory, see CMP0015.

Note that this command is rarely necessary.  Library locations
returned by find_package() and find_library() are absolute paths.
Pass these absolute library file paths directly to the
target_link_libraries() command.  CMake will ensure the linker finds
them.

list
----

List operations.

::

 list(LENGTH <list> <output variable>)
 list(GET <list> <element index> [<element index> ...]
      <output variable>)
 list(APPEND <list> [<element> ...])
 list(FIND <list> <value> <output variable>)
 list(INSERT <list> <element_index> <element> [<element> ...])
 list(REMOVE_ITEM <list> <value> [<value> ...])
 list(REMOVE_AT <list> <index> [<index> ...])
 list(REMOVE_DUPLICATES <list>)
 list(REVERSE <list>)
 list(SORT <list>)

LENGTH will return a given list's length.

GET will return list of elements specified by indices from the list.

APPEND will append elements to the list.

FIND will return the index of the element specified in the list or -1
if it wasn't found.

INSERT will insert elements to the list to the specified location.

REMOVE_AT and REMOVE_ITEM will remove items from the list.  The
difference is that REMOVE_ITEM will remove the given items, while
REMOVE_AT will remove the items at the given indices.

REMOVE_DUPLICATES will remove duplicated items in the list.

REVERSE reverses the contents of the list in-place.

SORT sorts the list in-place alphabetically.

The list subcommands APPEND, INSERT, REMOVE_AT, REMOVE_ITEM,
REMOVE_DUPLICATES, REVERSE and SORT may create new values for the list
within the current CMake variable scope.  Similar to the SET command,
the LIST command creates new variable values in the current scope,
even if the list itself is actually defined in a parent scope.  To
propagate the results of these operations upwards, use SET with
PARENT_SCOPE, SET with CACHE INTERNAL, or some other means of value
propagation.

NOTES: A list in cmake is a ; separated group of strings.  To create a
list the set command can be used.  For example, set(var a b c d e)
creates a list with a;b;c;d;e, and set(var "a b c d e") creates a
string or a list with one item in it.   (Note macro arguments are not
variables, and therefore cannot be used in LIST commands.)

When specifying index values, if <element index> is 0 or greater, it
is indexed from the beginning of the list, with 0 representing the
first list element.  If <element index> is -1 or lesser, it is indexed
from the end of the list, with -1 representing the last list element.
Be careful when counting with negative indices: they do not start from
0.  -0 is equivalent to 0, the first list element.

load_cache
----------

Load in the values from another project's CMake cache.

::

 load_cache(pathToCacheFile READ_WITH_PREFIX
            prefix entry1...)

Read the cache and store the requested entries in variables with their
name prefixed with the given prefix.  This only reads the values, and
does not create entries in the local project's cache.

::

 load_cache(pathToCacheFile [EXCLUDE entry1...]
            [INCLUDE_INTERNALS entry1...])

Load in the values from another cache and store them in the local
project's cache as internal entries.  This is useful for a project
that depends on another project built in a different tree.  EXCLUDE
option can be used to provide a list of entries to be excluded.
INCLUDE_INTERNALS can be used to provide a list of internal entries to
be included.  Normally, no internal entries are brought in.  Use of
this form of the command is strongly discouraged, but it is provided
for backward compatibility.

load_command
------------

Disallowed.  See CMake Policy ``CMP0031``.

Load a command into a running CMake.

::

 load_command(COMMAND_NAME <loc1> [loc2 ...])

The given locations are searched for a library whose name is
cmCOMMAND_NAME.  If found, it is loaded as a module and the command is
added to the set of available CMake commands.  Usually, TRY_COMPILE is
used before this command to compile the module.  If the command is
successfully loaded a variable named

::

 CMAKE_LOADED_COMMAND_<COMMAND_NAME>

will be set to the full path of the module that was loaded.  Otherwise
the variable will not be set.

macro
-----

Start recording a macro for later invocation as a command.

::

 macro(<name> [arg1 [arg2 [arg3 ...]]])
   COMMAND1(ARGS ...)
   COMMAND2(ARGS ...)
   ...
 endmacro(<name>)

Define a macro named <name> that takes arguments named arg1 arg2 arg3
(...).  Commands listed after macro, but before the matching endmacro,
are not invoked until the macro is invoked.  When it is invoked, the
commands recorded in the macro are first modified by replacing formal
parameters (``${arg1}``) with the arguments passed, and then invoked as
normal commands.  In addition to referencing the formal parameters you
can reference the values ``${ARGC}`` which will be set to the number of
arguments passed into the function as well as ``${ARGV0}`` ``${ARGV1}``
``${ARGV2}`` ...  which will have the actual values of the arguments
passed in.  This facilitates creating macros with optional arguments.
Additionally ``${ARGV}`` holds the list of all arguments given to the
macro and ``${ARGN}`` holds the list of arguments past the last expected
argument.

See the cmake_policy() command documentation for the behavior of
policies inside macros.

Macro Argument Caveats
^^^^^^^^^^^^^^^^^^^^^^

Note that the parameters to a macro and values such as ``ARGN`` are
not variables in the usual CMake sense.  They are string
replacements much like the C preprocessor would do with a macro.
Therefore you will NOT be able to use commands like::

 if(ARGV1) # ARGV1 is not a variable
 foreach(loop_var IN LISTS ARGN) # ARGN is not a variable

In the first case you can use ``if(${ARGV1})``, in the second case, you can
use ``foreach(loop_var ${ARGN})`` but this will skip empty arguments.
If you need to include them, you can use::

 set(list_var "${ARGN}")
 foreach(loop_var IN LISTS list_var)

Note that if you have a variable with the same name in the scope from
which the macro is called, using unreferenced names will use the
existing variable instead of the arguments. For example::

 macro(_BAR)
   foreach(arg IN LISTS ARGN)
     [...]
   endforeach()
 endmacro()

 function(_FOO)
   _bar(x y z)
 endfunction()

 _foo(a b c)

Will loop over ``a;b;c`` and not over ``x;y;z`` as one might be expecting.
If you want true CMake variables and/or better CMake scope control you
should look at the function command.

mark_as_advanced
----------------

Mark cmake cached variables as advanced.

::

 mark_as_advanced([CLEAR|FORCE] VAR [VAR2 ...])

Mark the named cached variables as advanced.  An advanced variable
will not be displayed in any of the cmake GUIs unless the show
advanced option is on.  If CLEAR is the first argument advanced
variables are changed back to unadvanced.  If FORCE is the first
argument, then the variable is made advanced.  If neither FORCE nor
CLEAR is specified, new values will be marked as advanced, but if the
variable already has an advanced/non-advanced state, it will not be
changed.

It does nothing in script mode.

math
----

Mathematical expressions.

::

 math(EXPR <output variable> <math expression>)

EXPR evaluates mathematical expression and returns result in the
output variable.  Example mathematical expression is '5 * ( 10 + 13
)'.  Supported operators are + - * / % | & ^ ~ << >> * / %.  They have
the same meaning as they do in C code.

message
-------

Display a message to the user.

::

 message([<mode>] "message to display" ...)

The optional <mode> keyword determines the type of message:

::

 (none)         = Important information
 STATUS         = Incidental information
 WARNING        = CMake Warning, continue processing
 AUTHOR_WARNING = CMake Warning (dev), continue processing
 SEND_ERROR     = CMake Error, continue processing,
                               but skip generation
 FATAL_ERROR    = CMake Error, stop processing and generation
 DEPRECATION    = CMake Deprecation Error or Warning if variable
                  CMAKE_ERROR_DEPRECATED or CMAKE_WARN_DEPRECATED
                  is enabled, respectively, else no message.

The CMake command-line tool displays STATUS messages on stdout and all
other message types on stderr.  The CMake GUI displays all messages in
its log area.  The interactive dialogs (ccmake and CMakeSetup) show
STATUS messages one at a time on a status line and other messages in
interactive pop-up boxes.

CMake Warning and Error message text displays using a simple markup
language.  Non-indented text is formatted in line-wrapped paragraphs
delimited by newlines.  Indented text is considered pre-formatted.

option
------

Provides an option that the user can optionally select.

::

 option(<option_variable> "help string describing option"
        [initial value])

Provide an option for the user to select as ON or OFF.  If no initial
value is provided, OFF is used.

If you have options that depend on the values of other options, see
the module help for CMakeDependentOption.

project
-------

Set a name, version, and enable languages for the entire project.

 project(<PROJECT-NAME> [LANGUAGES] [<language-name>...])
 project(<PROJECT-NAME>
         [VERSION <major>[.<minor>[.<patch>[.<tweak>]]]]
         [LANGUAGES <language-name>...])

Sets the name of the project and stores the name in the
``PROJECT_NAME`` variable.  Additionally this sets variables

* ``PROJECT_SOURCE_DIR``,
  ``<PROJECT-NAME>_SOURCE_DIR``
* ``PROJECT_BINARY_DIR``,
  ``<PROJECT-NAME>_BINARY_DIR``

If ``VERSION`` is specified, given components must be non-negative integers.
If ``VERSION`` is not specified, the default version is the empty string.
The ``VERSION`` option may not be used unless policy ``CMP0048`` is
set to ``NEW``.

The ``project()`` command stores the version number and its components
in variables

* ``PROJECT_VERSION``,
  ``<PROJECT-NAME>_VERSION``
* ``PROJECT_VERSION_MAJOR``,
  ``<PROJECT-NAME>_VERSION_MAJOR``
* ``PROJECT_VERSION_MINOR``,
  ``<PROJECT-NAME>_VERSION_MINOR``
* ``PROJECT_VERSION_PATCH``,
  ``<PROJECT-NAME>_VERSION_PATCH``
* ``PROJECT_VERSION_TWEAK``,
  ``<PROJECT-NAME>_VERSION_TWEAK``

Variables corresponding to unspecified versions are set to the empty string
(if policy ``CMP0048`` is set to ``NEW``).

Optionally you can specify which languages your project supports.
Example languages are ``C``, ``CXX`` (i.e.  C++), ``Fortran``, etc.
By default ``C`` and ``CXX`` are enabled if no language options are
given.  Specify language ``NONE``, or use the ``LANGUAGES`` keyword
and list no languages, to skip enabling any languages.

If a variable exists called ``CMAKE_PROJECT_<PROJECT-NAME>_INCLUDE``,
the file pointed to by that variable will be included as the last step of the
project command.

The top-level ``CMakeLists.txt`` file for a project must contain a
literal, direct call to the ``project()`` command; loading one
through the ``include()`` command is not sufficient.  If no such
call exists CMake will implicitly add one to the top that enables the
default languages (``C`` and ``CXX``).

qt_wrap_cpp
-----------

Create Qt Wrappers.

::

 qt_wrap_cpp(resultingLibraryName DestName
             SourceLists ...)

Produce moc files for all the .h files listed in the SourceLists.  The
moc files will be added to the library using the DestName source list.

qt_wrap_ui
----------

Create Qt user interfaces Wrappers.

::

 qt_wrap_ui(resultingLibraryName HeadersDestName
            SourcesDestName SourceLists ...)

Produce .h and .cxx files for all the .ui files listed in the
SourceLists.  The .h files will be added to the library using the
HeadersDestNamesource list.  The .cxx files will be added to the
library using the SourcesDestNamesource list.

remove_definitions
------------------

Removes -D define flags added by add_definitions.

::

 remove_definitions(-DFOO -DBAR ...)

Removes flags (added by add_definitions) from the compiler command
line for sources in the current directory and below.

return
------

Return from a file, directory or function.

::

 return()

Returns from a file, directory or function.  When this command is
encountered in an included file (via include() or find_package()), it
causes processing of the current file to stop and control is returned
to the including file.  If it is encountered in a file which is not
included by another file, e.g.  a CMakeLists.txt, control is returned
to the parent directory if there is one.  If return is called in a
function, control is returned to the caller of the function.  Note
that a macro is not a function and does not handle return like a
function does.

separate_arguments
------------------

Parse space-separated arguments into a semicolon-separated list.

::

 separate_arguments(<var> <UNIX|WINDOWS>_COMMAND "<args>")

Parses a unix- or windows-style command-line string "<args>" and
stores a semicolon-separated list of the arguments in <var>.  The
entire command line must be given in one "<args>" argument.

The UNIX_COMMAND mode separates arguments by unquoted whitespace.  It
recognizes both single-quote and double-quote pairs.  A backslash
escapes the next literal character (\" is "); there are no special
escapes (\n is just n).

The WINDOWS_COMMAND mode parses a windows command-line using the same
syntax the runtime library uses to construct argv at startup.  It
separates arguments by whitespace that is not double-quoted.
Backslashes are literal unless they precede double-quotes.  See the
MSDN article "Parsing C Command-Line Arguments" for details.

::

 separate_arguments(VARIABLE)

Convert the value of VARIABLE to a semi-colon separated list.  All
spaces are replaced with ';'.  This helps with generating command
lines.

set_directory_properties
------------------------

Set a property of the directory.

::

 set_directory_properties(PROPERTIES prop1 value1 prop2 value2)

Set a property for the current directory and subdirectories.  If the
property is not found, CMake will report an error.  The properties
include: INCLUDE_DIRECTORIES, LINK_DIRECTORIES,
INCLUDE_REGULAR_EXPRESSION, and ADDITIONAL_MAKE_CLEAN_FILES.
ADDITIONAL_MAKE_CLEAN_FILES is a list of files that will be cleaned as
a part of "make clean" stage.

set_property
------------

Set a named property in a given scope.

::

 set_property(<GLOBAL                            |
               DIRECTORY [dir]                   |
               TARGET    [target1 [target2 ...]] |
               SOURCE    [src1 [src2 ...]]       |
               TEST      [test1 [test2 ...]]     |
               CACHE     [entry1 [entry2 ...]]>
              [APPEND] [APPEND_STRING]
              PROPERTY <name> [value1 [value2 ...]])

Set one property on zero or more objects of a scope.  The first
argument determines the scope in which the property is set.  It must
be one of the following:

GLOBAL scope is unique and does not accept a name.

DIRECTORY scope defaults to the current directory but another
directory (already processed by CMake) may be named by full or
relative path.

TARGET scope may name zero or more existing targets.

SOURCE scope may name zero or more source files.  Note that source
file properties are visible only to targets added in the same
directory (CMakeLists.txt).

TEST scope may name zero or more existing tests.

CACHE scope must name zero or more cache existing entries.

The required PROPERTY option is immediately followed by the name of
the property to set.  Remaining arguments are used to compose the
property value in the form of a semicolon-separated list.  If the
APPEND option is given the list is appended to any existing property
value.If the APPEND_STRING option is given the string is append to any
existing property value as string, i.e.  it results in a longer string
and not a list of strings.

set
---

Set a CMake, cache or environment variable to a given value.

::

 set(<variable> <value>
     [[CACHE <type> <docstring> [FORCE]] | PARENT_SCOPE])

Within CMake sets <variable> to the value <value>.  <value> is
expanded before <variable> is set to it.  Normally, set will set a
regular CMake variable.  If CACHE is present, then the <variable> is
put in the cache instead, unless it is already in the cache.  See
section 'Variable types in CMake' below for details of regular and
cache variables and their interactions.  If CACHE is used, <type> and
<docstring> are required.  <type> is used by the CMake GUI to choose a
widget with which the user sets a value.  The value for <type> may be
one of

::

 FILEPATH = File chooser dialog.
 PATH     = Directory chooser dialog.
 STRING   = Arbitrary string.
 BOOL     = Boolean ON/OFF checkbox.
 INTERNAL = No GUI entry (used for persistent variables).

If <type> is INTERNAL, the cache variable is marked as internal, and
will not be shown to the user in tools like cmake-gui.  This is
intended for values that should be persisted in the cache, but which
users should not normally change.  INTERNAL implies FORCE.

Normally, set(...CACHE...) creates cache variables, but does not
modify them.  If FORCE is specified, the value of the cache variable
is set, even if the variable is already in the cache.  This should
normally be avoided, as it will remove any changes to the cache
variable's value by the user.

If PARENT_SCOPE is present, the variable will be set in the scope
above the current scope.  Each new directory or function creates a new
scope.  This command will set the value of a variable into the parent
directory or calling function (whichever is applicable to the case at
hand).  PARENT_SCOPE cannot be combined with CACHE.

If <value> is not specified then the variable is removed instead of
set.  See also: the unset() command.

::

 set(<variable> <value1> ... <valueN>)

In this case <variable> is set to a semicolon separated list of
values.

<variable> can be an environment variable such as:

::

 set( ENV{PATH} /home/martink )

in which case the environment variable will be set.

*** Variable types in CMake ***

In CMake there are two types of variables: normal variables and cache
variables.  Normal variables are meant for the internal use of the
script (just like variables in most programming languages); they are
not persisted across CMake runs.  Cache variables (unless set with
INTERNAL) are mostly intended for configuration settings where the
first CMake run determines a suitable default value, which the user
can then override, by editing the cache with tools such as ccmake or
cmake-gui.  Cache variables are stored in the CMake cache file, and
are persisted across CMake runs.

Both types can exist at the same time with the same name but different
values.  When ${FOO} is evaluated, CMake first looks for a normal
variable 'FOO' in scope and uses it if set.  If and only if no normal
variable exists then it falls back to the cache variable 'FOO'.

Some examples:

The code 'set(FOO "x")' sets the normal variable 'FOO'.  It does not
touch the cache, but it will hide any existing cache value 'FOO'.

The code 'set(FOO "x" CACHE ...)' checks for 'FOO' in the cache,
ignoring any normal variable of the same name.  If 'FOO' is in the
cache then nothing happens to either the normal variable or the cache
variable.  If 'FOO' is not in the cache, then it is added to the
cache.

Finally, whenever a cache variable is added or modified by a command,
CMake also *removes* the normal variable of the same name from the
current scope so that an immediately following evaluation of it will
expose the newly cached value.

Normally projects should avoid using normal and cache variables of the
same name, as this interaction can be hard to follow.  However, in
some situations it can be useful.  One example (used by some
projects):

A project has a subproject in its source tree.  The child project has
its own CMakeLists.txt, which is included from the parent
CMakeLists.txt using add_subdirectory().  Now, if the parent and the
child project provide the same option (for example a compiler option),
the parent gets the first chance to add a user-editable option to the
cache.  Normally, the child would then use the same value that the
parent uses.  However, it may be necessary to hard-code the value for
the child project's option while still allowing the user to edit the
value used by the parent project.  The parent project can achieve this
simply by setting a normal variable with the same name as the option
in a scope sufficient to hide the option's cache variable from the
child completely.  The parent has already set the cache variable, so
the child's set(...CACHE...) will do nothing, and evaluating the
option variable will use the value from the normal variable, which
hides the cache variable.

set_source_files_properties
---------------------------

Source files can have properties that affect how they are built.

::

 set_source_files_properties([file1 [file2 [...]]]
                             PROPERTIES prop1 value1
                             [prop2 value2 [...]])

Set properties associated with source files using a key/value paired
list.  See properties documentation for those known to CMake.
Unrecognized properties are ignored.  Source file properties are
visible only to targets added in the same directory (CMakeLists.txt).

set_target_properties
---------------------

Targets can have properties that affect how they are built.

::

 set_target_properties(target1 target2 ...
                       PROPERTIES prop1 value1
                       prop2 value2 ...)

Set properties on a target.  The syntax for the command is to list all
the files you want to change, and then provide the values you want to
set next.  You can use any prop value pair you want and extract it
later with the GET_TARGET_PROPERTY command.

Properties that affect the name of a target's output file are as
follows.  The PREFIX and SUFFIX properties override the default target
name prefix (such as "lib") and suffix (such as ".so").  IMPORT_PREFIX
and IMPORT_SUFFIX are the equivalent properties for the import library
corresponding to a DLL (for SHARED library targets).  OUTPUT_NAME sets
the real name of a target when it is built and can be used to help
create two targets of the same name even though CMake requires unique
logical target names.  There is also a <CONFIG>_OUTPUT_NAME that can
set the output name on a per-configuration basis.  <CONFIG>_POSTFIX
sets a postfix for the real name of the target when it is built under
the configuration named by <CONFIG> (in upper-case, such as
"DEBUG_POSTFIX").  The value of this property is initialized when the
target is created to the value of the variable CMAKE_<CONFIG>_POSTFIX
(except for executable targets because earlier CMake versions which
did not use this variable for executables).

The LINK_FLAGS property can be used to add extra flags to the link
step of a target.  LINK_FLAGS_<CONFIG> will add to the configuration
<CONFIG>, for example, DEBUG, RELEASE, MINSIZEREL, RELWITHDEBINFO.
DEFINE_SYMBOL sets the name of the preprocessor symbol defined when
compiling sources in a shared library.  If not set here then it is set
to target_EXPORTS by default (with some substitutions if the target is
not a valid C identifier).  This is useful for headers to know whether
they are being included from inside their library or outside to
properly setup dllexport/dllimport decorations.  The COMPILE_FLAGS
property sets additional compiler flags used to build sources within
the target.  It may also be used to pass additional preprocessor
definitions.

The LINKER_LANGUAGE property is used to change the tool used to link
an executable or shared library.  The default is set the language to
match the files in the library.  CXX and C are common values for this
property.

For shared libraries VERSION and SOVERSION can be used to specify the
build version and API version respectively.  When building or
installing appropriate symlinks are created if the platform supports
symlinks and the linker supports so-names.  If only one of both is
specified the missing is assumed to have the same version number.  For
executables VERSION can be used to specify the build version.  When
building or installing appropriate symlinks are created if the
platform supports symlinks.  For shared libraries and executables on
Windows the VERSION attribute is parsed to extract a "major.minor"
version number.  These numbers are used as the image version of the
binary.

There are a few properties used to specify RPATH rules.  INSTALL_RPATH
is a semicolon-separated list specifying the rpath to use in installed
targets (for platforms that support it).  INSTALL_RPATH_USE_LINK_PATH
is a boolean that if set to true will append directories in the linker
search path and outside the project to the INSTALL_RPATH.
SKIP_BUILD_RPATH is a boolean specifying whether to skip automatic
generation of an rpath allowing the target to run from the build tree.
BUILD_WITH_INSTALL_RPATH is a boolean specifying whether to link the
target in the build tree with the INSTALL_RPATH.  This takes
precedence over SKIP_BUILD_RPATH and avoids the need for relinking
before installation.  INSTALL_NAME_DIR is a string specifying the
directory portion of the "install_name" field of shared libraries on
Mac OSX to use in the installed targets.  When the target is created
the values of the variables CMAKE_INSTALL_RPATH,
CMAKE_INSTALL_RPATH_USE_LINK_PATH, CMAKE_SKIP_BUILD_RPATH,
CMAKE_BUILD_WITH_INSTALL_RPATH, and CMAKE_INSTALL_NAME_DIR are used to
initialize these properties.

PROJECT_LABEL can be used to change the name of the target in an IDE
like visual studio.  VS_KEYWORD can be set to change the visual studio
keyword, for example Qt integration works better if this is set to
Qt4VSv1.0.

VS_SCC_PROJECTNAME, VS_SCC_LOCALPATH, VS_SCC_PROVIDER and
VS_SCC_AUXPATH can be set to add support for source control bindings
in a Visual Studio project file.

VS_GLOBAL_<variable> can be set to add a Visual Studio
project-specific global variable.  Qt integration works better if
VS_GLOBAL_QtVersion is set to the Qt version FindQt4.cmake found.  For
example, "4.7.3"

The PRE_INSTALL_SCRIPT and POST_INSTALL_SCRIPT properties are the old
way to specify CMake scripts to run before and after installing a
target.  They are used only when the old INSTALL_TARGETS command is
used to install the target.  Use the INSTALL command instead.

The EXCLUDE_FROM_DEFAULT_BUILD property is used by the visual studio
generators.  If it is set to 1 the target will not be part of the
default build when you select "Build Solution".  This can also be set
on a per-configuration basis using
EXCLUDE_FROM_DEFAULT_BUILD_<CONFIG>.

set_tests_properties
--------------------

Set a property of the tests.

::

 set_tests_properties(test1 [test2...] PROPERTIES prop1 value1 prop2 value2)

Set a property for the tests.  If the property is not found, CMake
will report an error.  Generator expressions will be expanded the same
as supported by the test's add_test call.  The properties include:

WILL_FAIL: If set to true, this will invert the pass/fail flag of the
test.

PASS_REGULAR_EXPRESSION: If set, the test output will be checked
against the specified regular expressions and at least one of the
regular expressions has to match, otherwise the test will fail.

::

 Example: PASS_REGULAR_EXPRESSION "TestPassed;All ok"

FAIL_REGULAR_EXPRESSION: If set, if the output will match to one of
specified regular expressions, the test will fail.

::

 Example: PASS_REGULAR_EXPRESSION "[^a-z]Error;ERROR;Failed"

Both PASS_REGULAR_EXPRESSION and FAIL_REGULAR_EXPRESSION expect a list
of regular expressions.

TIMEOUT: Setting this will limit the test runtime to the number of
seconds specified.

site_name
---------

Set the given variable to the name of the computer.

::

 site_name(variable)

source_group
------------

Define a grouping for source files in IDE project generation.

 source_group(<name> [FILES <src>...] [REGULAR_EXPRESSION <regex>])

Defines a group into which sources will be placed in project files.
This is intended to set up file tabs in Visual Studio.
The options are:

``FILES``
 Any source file specified explicitly will be placed in group
 ``<name>``.  Relative paths are interpreted with respect to the
 current source directory.

``REGULAR_EXPRESSION``
 Any source file whose name matches the regular expression will
 be placed in group ``<name>``.

If a source file matches multiple groups, the *last* group that
explicitly lists the file with ``FILES`` will be favored, if any.
If no group explicitly lists the file, the *last* group whose
regular expression matches the file will be favored.

The ``<name>`` of the group may contain backslashes to specify subgroups:

 source_group(outer\\inner ...)

For backwards compatibility, the short-hand signature

 source_group(<name> <regex>)

is equivalent to

 source_group(<name> REGULAR_EXPRESSION <regex>)

string
------

String operations.

::

 string(REGEX MATCH <regular_expression>
        <output variable> <input> [<input>...])
 string(REGEX MATCHALL <regular_expression>
        <output variable> <input> [<input>...])
 string(REGEX REPLACE <regular_expression>
        <replace_expression> <output variable>
        <input> [<input>...])
 string(REPLACE <match_string>
        <replace_string> <output variable>
        <input> [<input>...])
 string(CONCAT <output variable> [<input>...])
 string(<MD5|SHA1|SHA224|SHA256|SHA384|SHA512>
        <output variable> <input>)
 string(COMPARE EQUAL <string1> <string2> <output variable>)
 string(COMPARE NOTEQUAL <string1> <string2> <output variable>)
 string(COMPARE LESS <string1> <string2> <output variable>)
 string(COMPARE GREATER <string1> <string2> <output variable>)
 string(ASCII <number> [<number> ...] <output variable>)
 string(CONFIGURE <string1> <output variable>
        [@ONLY] [ESCAPE_QUOTES])
 string(TOUPPER <string1> <output variable>)
 string(TOLOWER <string1> <output variable>)
 string(LENGTH <string> <output variable>)
 string(SUBSTRING <string> <begin> <length> <output variable>)
 string(STRIP <string> <output variable>)
 string(RANDOM [LENGTH <length>] [ALPHABET <alphabet>]
        [RANDOM_SEED <seed>] <output variable>)
 string(FIND <string> <substring> <output variable> [REVERSE])
 string(TIMESTAMP <output variable> [<format string>] [UTC])
 string(MAKE_C_IDENTIFIER <input string> <output variable>)

REGEX MATCH will match the regular expression once and store the match
in the output variable.

REGEX MATCHALL will match the regular expression as many times as
possible and store the matches in the output variable as a list.

REGEX REPLACE will match the regular expression as many times as
possible and substitute the replacement expression for the match in
the output.  The replace expression may refer to paren-delimited
subexpressions of the match using \1, \2, ..., \9.  Note that two
backslashes (\\1) are required in CMake code to get a backslash
through argument parsing.

REPLACE will replace all occurrences of match_string in the input with
replace_string and store the result in the output.

CONCAT will concatenate all the input arguments together and store
the result in the named output variable.

MD5, SHA1, SHA224, SHA256, SHA384, and SHA512 will compute a
cryptographic hash of the input string.

COMPARE EQUAL/NOTEQUAL/LESS/GREATER will compare the strings and store
true or false in the output variable.

ASCII will convert all numbers into corresponding ASCII characters.

CONFIGURE will transform a string like CONFIGURE_FILE transforms a
file.

TOUPPER/TOLOWER will convert string to upper/lower characters.

LENGTH will return a given string's length.

SUBSTRING will return a substring of a given string.  If length is -1
the remainder of the string starting at begin will be returned.

STRIP will return a substring of a given string with leading and
trailing spaces removed.

RANDOM will return a random string of given length consisting of
characters from the given alphabet.  Default length is 5 characters
and default alphabet is all numbers and upper and lower case letters.
If an integer RANDOM_SEED is given, its value will be used to seed the
random number generator.

FIND will return the position where the given substring was found in
the supplied string.  If the REVERSE flag was used, the command will
search for the position of the last occurrence of the specified
substring.

The following characters have special meaning in regular expressions:

::

 ^         Matches at beginning of input
 $         Matches at end of input
 .         Matches any single character
 [ ]       Matches any character(s) inside the brackets
 [^ ]      Matches any character(s) not inside the brackets
  -        Inside brackets, specifies an inclusive range between
           characters on either side e.g. [a-f] is [abcdef]
           To match a literal - using brackets, make it the first
           or the last character e.g. [+*/-] matches basic
           mathematical operators.
 *         Matches preceding pattern zero or more times
 +         Matches preceding pattern one or more times
 ?         Matches preceding pattern zero or once only
 |         Matches a pattern on either side of the |
 ()        Saves a matched subexpression, which can be referenced
           in the REGEX REPLACE operation. Additionally it is saved
           by all regular expression-related commands, including
           e.g. if( MATCHES ), in the variables CMAKE_MATCH_(0..9).

``*``, ``+`` and ``?`` have higher precedence than concatenation.  | has lower
precedence than concatenation.  This means that the regular expression
"^ab+d$" matches "abbd" but not "ababd", and the regular expression
"^(ab|cd)$" matches "ab" but not "abd".

TIMESTAMP will write a string representation of the current date
and/or time to the output variable.

Should the command be unable to obtain a timestamp the output variable
will be set to the empty string "".

The optional UTC flag requests the current date/time representation to
be in Coordinated Universal Time (UTC) rather than local time.

The optional <format string> may contain the following format
specifiers:

::

 %d        The day of the current month (01-31).
 %H        The hour on a 24-hour clock (00-23).
 %I        The hour on a 12-hour clock (01-12).
 %j        The day of the current year (001-366).
 %m        The month of the current year (01-12).
 %M        The minute of the current hour (00-59).
 %S        The second of the current minute.
           60 represents a leap second. (00-60)
 %U        The week number of the current year (00-53).
 %w        The day of the current week. 0 is Sunday. (0-6)
 %y        The last two digits of the current year (00-99)
 %Y        The current year.

Unknown format specifiers will be ignored and copied to the output
as-is.

If no explicit <format string> is given it will default to:

::

 %Y-%m-%dT%H:%M:%S    for local time.
 %Y-%m-%dT%H:%M:%SZ   for UTC.

MAKE_C_IDENTIFIER will write a string which can be used as an
identifier in C.

target_compile_definitions
--------------------------

Add compile definitions to a target.

::

 target_compile_definitions(<target>
   <INTERFACE|PUBLIC|PRIVATE> [items1...]
   [<INTERFACE|PUBLIC|PRIVATE> [items2...] ...])

Specify compile definitions to use when compiling a given <target.  The
named ``<target>`` must have been created by a command such as
``add_executable()`` or ``add_library()`` and must not be an
:ref:`Imported Target <Imported Targets>`.

The ``INTERFACE``, ``PUBLIC`` and ``PRIVATE`` keywords are required to
specify the scope of the following arguments.  ``PRIVATE`` and ``PUBLIC``
items will populate the ``COMPILE_DEFINITIONS`` property of
``<target>``. ``PUBLIC`` and ``INTERFACE`` items will populate the
``INTERFACE_COMPILE_DEFINITIONS`` property of ``<target>``.  The
following arguments specify compile definitions.  Repeated calls for the
same ``<target>`` append items in the order called.

Arguments to ``target_compile_definitions`` may use "generator expressions"
with the syntax ``$<...>``.  See the ``cmake-generator-expressions(7)``
manual for available expressions.  See the ``cmake-buildsystem(7)``
manual for more on defining buildsystem properties.

target_compile_options
----------------------

Add compile options to a target.

::

 target_compile_options(<target> [BEFORE]
   <INTERFACE|PUBLIC|PRIVATE> [items1...]
   [<INTERFACE|PUBLIC|PRIVATE> [items2...] ...])

Specify compile options to use when compiling a given target.  The
named ``<target>`` must have been created by a command such as
``add_executable()`` or ``add_library()`` and must not be an
``IMPORTED Target``.  If ``BEFORE`` is specified, the content will
be prepended to the property instead of being appended.

This command can be used to add any options, but
alternative commands exist to add preprocessor definitions
(``target_compile_definitions()`` and ``add_definitions()``) or
include directories (``target_include_directories()`` and
``include_directories()``).  See documentation of the
``directory`` and
`` target`` ``COMPILE_OPTIONS`` properties.

The ``INTERFACE``, ``PUBLIC`` and ``PRIVATE`` keywords are required to
specify the scope of the following arguments.  ``PRIVATE`` and ``PUBLIC``
items will populate the ``COMPILE_OPTIONS`` property of
``<target>``.  ``PUBLIC`` and ``INTERFACE`` items will populate the
``INTERFACE_COMPILE_OPTIONS`` property of ``<target>``.  The
following arguments specify compile options.  Repeated calls for the same
``<target>`` append items in the order called.

Arguments to ``target_compile_options`` may use "generator expressions"
with the syntax ``$<...>``. See the ``cmake-generator-expressions(7)``
manual for available expressions.  See the ``cmake-buildsystem(7)``
manual for more on defining buildsystem properties.

target_include_directories
--------------------------

Add include directories to a target.

::

 target_include_directories(<target> [SYSTEM] [BEFORE]
   <INTERFACE|PUBLIC|PRIVATE> [items1...]
   [<INTERFACE|PUBLIC|PRIVATE> [items2...] ...])

Specify include directories or targets to use when compiling a given
target.  The named ``<target>`` must have been created by a command such
as ``add_executable()`` or ``add_library()`` and must not be an
``IMPORTED`` target.

If ``BEFORE`` is specified, the content will be prepended to the property
instead of being appended.

The ``INTERFACE``, ``PUBLIC`` and ``PRIVATE`` keywords are required to specify
the scope of the following arguments.  ``PRIVATE`` and ``PUBLIC`` items will
populate the ``INCLUDE_DIRECTORIES`` property of ``<target>``.
``PUBLIC`` and ``INTERFACE`` items will populate the
``INTERFACE_INCLUDE_DIRECTORIES``
property of ``<target>``.  The following arguments specify include
directories.

Specified include directories may be absolute paths or relative paths.
Repeated calls for the same <target> append items in the order called.  If
``SYSTEM`` is specified, the compiler will be told the
directories are meant as system include directories on some platforms
(signalling this setting might achieve effects such as the compiler
skipping warnings, or these fixed-install system files not being
considered in dependency calculations - see compiler docs).  If ``SYSTEM``
is used together with ``PUBLIC`` or ``INTERFACE``, the
``INTERFACE_SYSTEM_INCLUDE_DIRECTORIES`` target property will be
populated with the specified directories.

Arguments to ``target_include_directories`` may use "generator expressions"
with the syntax ``$<...>``.  See the ``cmake-generator-expressions(7)``
manual for available expressions.  See the ``cmake-buildsystem(7)``
manual for more on defining buildsystem properties.

Include directories usage requirements commonly differ between the build-tree
and the install-tree.  The ``BUILD_INTERFACE`` and ``INSTALL_INTERFACE``
generator expressions can be used to describe separate usage requirements
based on the usage location.  Relative paths are allowed within the
``INSTALL_INTERFACE`` expression and are interpreted relative to the
installation prefix.  For example:

 target_include_directories(mylib PUBLIC
   $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include/mylib>
   $<INSTALL_INTERFACE:include/mylib>  # <prefix>/include/mylib
 )

target_link_libraries
---------------------

Link a target to given libraries.

::

 target_link_libraries(<target> [item1 [item2 [...]]]
                       [[debug|optimized|general] <item>] ...)

Specify libraries or flags to use when linking a given target.  The
named ``<target>`` must have been created in the current directory by a
command such as ``add_executable()`` or ``add_library()``.  The
remaining arguments specify library names or flags.  Repeated calls for
the same ``<target>`` append items in the order called.

If a library name matches that of another target in the project a
dependency will automatically be added in the build system to make sure
the library being linked is up-to-date before the target links. Item names
starting with ``-``, but not ``-l`` or ``-framework``, are treated as
linker flags.

A ``debug``, ``optimized``, or ``general`` keyword indicates that the
library immediately following it is to be used only for the
corresponding build configuration.  The ``debug`` keyword corresponds to
the Debug configuration (or to configurations named in the
``DEBUG_CONFIGURATIONS`` global property if it is set).  The
``optimized`` keyword corresponds to all other configurations.  The
``general`` keyword corresponds to all configurations, and is purely
optional (assumed if omitted).  Higher granularity may be achieved for
per-configuration rules by creating and linking to
:ref:`IMPORTED library targets <Imported Targets>`.

Library dependencies are transitive by default with this signature.
When this target is linked into another target then the libraries
linked to this target will appear on the link line for the other
target too.  This transitive "link interface" is stored in the
``INTERFACE_LINK_LIBRARIES`` target property and may be overridden
by setting the property directly.  When ``CMP0022`` is not set to
``NEW``, transitive linking is built in but may be overridden by the
``LINK_INTERFACE_LIBRARIES`` property.  Calls to other signatures
of this command may set the property making any libraries linked
exclusively by this signature private.

CMake will also propagate :ref:`usage requirements <Target Usage Requirements>`
from linked library targets.  Usage requirements of dependencies affect
compilation of sources in the ``<target>``.

If an ``<item>`` is a library in a Mac OX framework, the ``Headers``
directory of the framework will also be processed as a
:ref:`usage requirement <Target Usage Requirements>`.  This has the same
effect as passing the framework directory as an include directory.

--------------------------------------------------------------------------

::

 target_link_libraries(<target>
                     <PRIVATE|PUBLIC|INTERFACE> <lib> ...
                     [<PRIVATE|PUBLIC|INTERFACE> <lib> ... ] ...])

The ``PUBLIC``, ``PRIVATE`` and ``INTERFACE`` keywords can be used to
specify both the link dependencies and the link interface in one command.
Libraries and targets following ``PUBLIC`` are linked to, and are made
part of the link interface.  Libraries and targets following ``PRIVATE``
are linked to, but are not made part of the link interface.  Libraries
following ``INTERFACE`` are appended to the link interface and are not
used for linking ``<target>``.

--------------------------------------------------------------------------

::

 target_link_libraries(<target> LINK_INTERFACE_LIBRARIES
                       [[debug|optimized|general] <lib>] ...)

The ``LINK_INTERFACE_LIBRARIES`` mode appends the libraries to the
``INTERFACE_LINK_LIBRARIES`` target property instead of using them
for linking.  If policy ``CMP0022`` is not ``NEW``, then this mode
also appends libraries to the ``LINK_INTERFACE_LIBRARIES`` and its
per-configuration equivalent.

This signature is for compatibility only.  Prefer the ``INTERFACE`` mode
instead.

Libraries specified as ``debug`` are wrapped in a generator expression to
correspond to debug builds.  If policy ``CMP0022`` is
not ``NEW``, the libraries are also appended to the
``LINK_INTERFACE_LIBRARIES_DEBUG``
property (or to the properties corresponding to configurations listed in
the ``DEBUG_CONFIGURATIONS`` global property if it is set).
Libraries specified as ``optimized`` are appended to the
``INTERFACE_LINK_LIBRARIES`` property.  If policy ``CMP0022``
is not ``NEW``, they are also appended to the
``LINK_INTERFACE_LIBRARIES`` property.  Libraries specified as
``general`` (or without any keyword) are treated as if specified for both
``debug`` and ``optimized``.

--------------------------------------------------------------------------

::

 target_link_libraries(<target>
                       <LINK_PRIVATE|LINK_PUBLIC>
                         [[debug|optimized|general] <lib>] ...
                       [<LINK_PRIVATE|LINK_PUBLIC>
                         [[debug|optimized|general] <lib>] ...])

The ``LINK_PUBLIC`` and ``LINK_PRIVATE`` modes can be used to specify both
the link dependencies and the link interface in one command.

This signature is for compatibility only.  Prefer the ``PUBLIC`` or
``PRIVATE`` keywords instead.

Libraries and targets following ``LINK_PUBLIC`` are linked to, and are
made part of the ``INTERFACE_LINK_LIBRARIES``.  If policy
``CMP0022`` is not ``NEW``, they are also made part of the
``LINK_INTERFACE_LIBRARIES``.  Libraries and targets following
``LINK_PRIVATE`` are linked to, but are not made part of the
``INTERFACE_LINK_LIBRARIES`` (or ``LINK_INTERFACE_LIBRARIES``).

The library dependency graph is normally acyclic (a DAG), but in the case
of mutually-dependent ``STATIC`` libraries CMake allows the graph to
contain cycles (strongly connected components).  When another target links
to one of the libraries, CMake repeats the entire connected component.
For example, the code

 add_library(A STATIC a.c)
 add_library(B STATIC b.c)
 target_link_libraries(A B)
 target_link_libraries(B A)
 add_executable(main main.c)
 target_link_libraries(main A)

links ``main`` to ``A B A B``.  While one repetition is usually
sufficient, pathological object file and symbol arrangements can require
more.  One may handle such cases by manually repeating the component in
the last ``target_link_libraries`` call.  However, if two archives are
really so interdependent they should probably be combined into a single
archive.

Arguments to target_link_libraries may use "generator expressions"
with the syntax ``$<...>``.  Note however, that generator expressions
will not be used in OLD handling of ``CMP0003`` or ``CMP0004``.
See the ``cmake-generator-expressions(7)`` manual for available
expressions.  See the ``cmake-buildsystem(7)`` manual for more on
defining buildsystem properties.

try_compile
-----------

Try building some code.

::

 try_compile(RESULT_VAR <bindir> <srcdir>
             <projectName> [targetName] [CMAKE_FLAGS flags...]
             [OUTPUT_VARIABLE <var>])

Try building a project.  In this form, srcdir should contain a
complete CMake project with a CMakeLists.txt file and all sources.
The bindir and srcdir will not be deleted after this command is run.
Specify targetName to build a specific target instead of the 'all' or
'ALL_BUILD' target.

::

 try_compile(RESULT_VAR <bindir> <srcfile|SOURCES srcfile...>
             [CMAKE_FLAGS flags...]
             [COMPILE_DEFINITIONS flags...]
             [LINK_LIBRARIES libs...]
             [OUTPUT_VARIABLE <var>]
             [COPY_FILE <fileName> [COPY_FILE_ERROR <var>]])

Try building an executable from one or more source files.  In this
form the user need only supply one or more source files that include a
definition for 'main'.  CMake will create a CMakeLists.txt file to
build the source(s) as an executable.  Specify COPY_FILE to get a copy
of the linked executable at the given fileName and optionally
COPY_FILE_ERROR to capture any error.

In this version all files in bindir/CMakeFiles/CMakeTmp will be
cleaned automatically.  For debugging, --debug-trycompile can be
passed to cmake to avoid this clean.  However, multiple sequential
try_compile operations reuse this single output directory.  If you use
--debug-trycompile, you can only debug one try_compile call at a time.
The recommended procedure is to configure with cmake all the way
through once, then delete the cache entry associated with the
try_compile call of interest, and then re-run cmake again with
--debug-trycompile.

Some extra flags that can be included are, INCLUDE_DIRECTORIES,
LINK_DIRECTORIES, and LINK_LIBRARIES.  COMPILE_DEFINITIONS are
-Ddefinition that will be passed to the compile line.

The srcfile signature also accepts a LINK_LIBRARIES argument which may
contain a list of libraries or IMPORTED targets which will be linked
to in the generated project.  If LINK_LIBRARIES is specified as a
parameter to try_compile, then any LINK_LIBRARIES passed as
CMAKE_FLAGS will be ignored.

try_compile creates a CMakeList.txt file on the fly that looks like
this:

::

 add_definitions( <expanded COMPILE_DEFINITIONS from calling cmake>)
 include_directories(${INCLUDE_DIRECTORIES})
 link_directories(${LINK_DIRECTORIES})
 add_executable(cmTryCompileExec sources)
 target_link_libraries(cmTryCompileExec ${LINK_LIBRARIES})

In both versions of the command, if OUTPUT_VARIABLE is specified, then
the output from the build process is stored in the given variable.
The success or failure of the try_compile, i.e.  TRUE or FALSE
respectively, is returned in RESULT_VAR.  CMAKE_FLAGS can be used to
pass -DVAR:TYPE=VALUE flags to the cmake that is run during the build.
Set variable CMAKE_TRY_COMPILE_CONFIGURATION to choose a build
configuration.

try_run
-------

Try compiling and then running some code.

::

 try_run(RUN_RESULT_VAR COMPILE_RESULT_VAR
         bindir srcfile [CMAKE_FLAGS <Flags>]
         [COMPILE_DEFINITIONS <flags>]
         [COMPILE_OUTPUT_VARIABLE comp]
         [RUN_OUTPUT_VARIABLE run]
         [OUTPUT_VARIABLE var]
         [ARGS <arg1> <arg2>...])

Try compiling a srcfile.  Return TRUE or FALSE for success or failure
in COMPILE_RESULT_VAR.  Then if the compile succeeded, run the
executable and return its exit code in RUN_RESULT_VAR.  If the
executable was built, but failed to run, then RUN_RESULT_VAR will be
set to FAILED_TO_RUN.  COMPILE_OUTPUT_VARIABLE specifies the variable
where the output from the compile step goes.  RUN_OUTPUT_VARIABLE
specifies the variable where the output from the running executable
goes.

For compatibility reasons OUTPUT_VARIABLE is still supported, which
gives you the output from the compile and run step combined.

Cross compiling issues

When cross compiling, the executable compiled in the first step
usually cannot be run on the build host.  try_run() checks the
CMAKE_CROSSCOMPILING variable to detect whether CMake is in
crosscompiling mode.  If that's the case, it will still try to compile
the executable, but it will not try to run the executable.  Instead it
will create cache variables which must be filled by the user or by
presetting them in some CMake script file to the values the executable
would have produced if it had been run on its actual target platform.
These variables are RUN_RESULT_VAR (explanation see above) and if
RUN_OUTPUT_VARIABLE (or OUTPUT_VARIABLE) was used, an additional cache
variable RUN_RESULT_VAR__COMPILE_RESULT_VAR__TRYRUN_OUTPUT.This is
intended to hold stdout and stderr from the executable.

In order to make cross compiling your project easier, use try_run only
if really required.  If you use try_run, use RUN_OUTPUT_VARIABLE (or
OUTPUT_VARIABLE) only if really required.  Using them will require
that when crosscompiling, the cache variables will have to be set
manually to the output of the executable.  You can also "guard" the
calls to try_run with if(CMAKE_CROSSCOMPILING) and provide an
easy-to-preset alternative for this case.

Set variable CMAKE_TRY_COMPILE_CONFIGURATION to choose a build
configuration.

unset
-----

Unset a variable, cache variable, or environment variable.

::

 unset(<variable> [CACHE | PARENT_SCOPE])

Removes the specified variable causing it to become undefined.  If
CACHE is present then the variable is removed from the cache instead
of the current scope.

If PARENT_SCOPE is present then the variable is removed from the scope
above the current scope.  See the same option in the set() command for
further details.

<variable> can be an environment variable such as:

::

 unset(ENV{LD_LIBRARY_PATH})

in which case the variable will be removed from the current
environment.

variable_watch
--------------

Watch the CMake variable for change.

::

 variable_watch(<variable name> [<command to execute>])

If the specified variable changes, the message will be printed about
the variable being changed.  If the command is specified, the command
will be executed.  The command will receive the following arguments:
COMMAND(<variable> <access> <value> <current list file> <stack>)

while
-----

Evaluate a group of commands while a condition is true

::

 while(condition)
   COMMAND1(ARGS ...)
   COMMAND2(ARGS ...)
   ...
 endwhile(condition)

All commands between while and the matching endwhile are recorded
without being invoked.  Once the endwhile is evaluated, the recorded
list of commands is invoked as long as the condition is true.  The
condition is evaluated using the same logic as the if command.

Deprecated Commands
===================

These commands are available only for compatibility with older
versions of CMake.  Do not use them in new code.

build_name
----------

Disallowed.  See CMake Policy ``CMP0036``.

Use ${CMAKE_SYSTEM} and ${CMAKE_CXX_COMPILER} instead.

::

 build_name(variable)

Sets the specified variable to a string representing the platform and
compiler settings.  These values are now available through the
CMAKE_SYSTEM and CMAKE_CXX_COMPILER variables.

exec_program
------------

Deprecated.  Use the execute_process() command instead.

Run an executable program during the processing of the CMakeList.txt
file.

::

 exec_program(Executable [directory in which to run]
              [ARGS <arguments to executable>]
              [OUTPUT_VARIABLE <var>]
              [RETURN_VALUE <var>])

The executable is run in the optionally specified directory.  The
executable can include arguments if it is double quoted, but it is
better to use the optional ARGS argument to specify arguments to the
program.  This is because cmake will then be able to escape spaces in
the executable path.  An optional argument OUTPUT_VARIABLE specifies a
variable in which to store the output.  To capture the return value of
the execution, provide a RETURN_VALUE.  If OUTPUT_VARIABLE is
specified, then no output will go to the stdout/stderr of the console
running cmake.

export_library_dependencies
---------------------------

Disallowed.  See CMake Policy ``CMP0033``.

Use ``install(EXPORT)`` or ``export()`` command.

This command generates an old-style library dependencies file.
Projects requiring CMake 2.6 or later should not use the command.  Use
instead the install(EXPORT) command to help export targets from an
installation tree and the export() command to export targets from a
build tree.

The old-style library dependencies file does not take into account
per-configuration names of libraries or the LINK_INTERFACE_LIBRARIES
target property.

::

 export_library_dependencies(<file> [APPEND])

Create a file named <file> that can be included into a CMake listfile
with the INCLUDE command.  The file will contain a number of SET
commands that will set all the variables needed for library dependency
information.  This should be the last command in the top level
CMakeLists.txt file of the project.  If the APPEND option is
specified, the SET commands will be appended to the given file instead
of replacing it.

install_files
-------------

Deprecated.  Use the install(FILES ) command instead.

This command has been superceded by the install command.  It is
provided for compatibility with older CMake code.  The FILES form is
directly replaced by the FILES form of the install command.  The
regexp form can be expressed more clearly using the GLOB form of the
file command.

::

 install_files(<dir> extension file file ...)

Create rules to install the listed files with the given extension into
the given directory.  Only files existing in the current source tree
or its corresponding location in the binary tree may be listed.  If a
file specified already has an extension, that extension will be
removed first.  This is useful for providing lists of source files
such as foo.cxx when you want the corresponding foo.h to be installed.
A typical extension is '.h'.

::

 install_files(<dir> regexp)

Any files in the current source directory that match the regular
expression will be installed.

::

 install_files(<dir> FILES file file ...)

Any files listed after the FILES keyword will be installed explicitly
from the names given.  Full paths are allowed in this form.

The directory <dir> is relative to the installation prefix, which is
stored in the variable CMAKE_INSTALL_PREFIX.

install_programs
----------------

Deprecated. Use the install(PROGRAMS ) command instead.

This command has been superceded by the install command.  It is
provided for compatibility with older CMake code.  The FILES form is
directly replaced by the PROGRAMS form of the INSTALL command.  The
regexp form can be expressed more clearly using the GLOB form of the
FILE command.

::

 install_programs(<dir> file1 file2 [file3 ...])
 install_programs(<dir> FILES file1 [file2 ...])

Create rules to install the listed programs into the given directory.
Use the FILES argument to guarantee that the file list version of the
command will be used even when there is only one argument.

::

 install_programs(<dir> regexp)

In the second form any program in the current source directory that
matches the regular expression will be installed.

This command is intended to install programs that are not built by
cmake, such as shell scripts.  See the TARGETS form of the INSTALL
command to create installation rules for targets built by cmake.

The directory <dir> is relative to the installation prefix, which is
stored in the variable CMAKE_INSTALL_PREFIX.

install_targets
---------------

Deprecated. Use the install(TARGETS )  command instead.

This command has been superceded by the install command.  It is
provided for compatibility with older CMake code.

::

 install_targets(<dir> [RUNTIME_DIRECTORY dir] target target)

Create rules to install the listed targets into the given directory.
The directory <dir> is relative to the installation prefix, which is
stored in the variable CMAKE_INSTALL_PREFIX.  If RUNTIME_DIRECTORY is
specified, then on systems with special runtime files (Windows DLL),
the files will be copied to that directory.

link_libraries
--------------

Deprecated. Use the target_link_libraries() command instead.

Link libraries to all targets added later.

::

 link_libraries(library1 <debug | optimized> library2 ...)

Specify a list of libraries to be linked into any following targets
(typically added with the add_executable or add_library calls).  This
command is passed down to all subdirectories.  The debug and optimized
strings may be used to indicate that the next library listed is to be
used only for that specific type of build.

make_directory
--------------

Deprecated. Use the file(MAKE_DIRECTORY ) command instead.

::

 make_directory(directory)

Creates the specified directory.  Full paths should be given.  Any
parent directories that do not exist will also be created.  Use with
care.

output_required_files
---------------------

Disallowed.  See CMake Policy ``CMP0032``.

Approximate C preprocessor dependency scanning.

This command exists only because ancient CMake versions provided it.
CMake handles preprocessor dependency scanning automatically using a
more advanced scanner.

::

 output_required_files(srcfile outputfile)

Outputs a list of all the source files that are required by the
specified srcfile.  This list is written into outputfile.  This is
similar to writing out the dependencies for srcfile except that it
jumps from .h files into .cxx, .c and .cpp files if possible.

remove
------

Deprecated. Use the list(REMOVE_ITEM ) command instead.

::

 remove(VAR VALUE VALUE ...)

Removes VALUE from the variable VAR.  This is typically used to remove
entries from a vector (e.g.  semicolon separated list).  VALUE is
expanded.

subdir_depends
--------------

Disallowed.  See CMake Policy ``CMP0029``.

Does nothing.

::

 subdir_depends(subdir dep1 dep2 ...)

Does not do anything.  This command used to help projects order
parallel builds correctly.  This functionality is now automatic.

subdirs
-------

Deprecated. Use the add_subdirectory() command instead.

Add a list of subdirectories to the build.

::

 subdirs(dir1 dir2 ...[EXCLUDE_FROM_ALL exclude_dir1 exclude_dir2 ...]
         [PREORDER] )

Add a list of subdirectories to the build.  The add_subdirectory
command should be used instead of subdirs although subdirs will still
work.  This will cause any CMakeLists.txt files in the sub directories
to be processed by CMake.  Any directories after the PREORDER flag are
traversed first by makefile builds, the PREORDER flag has no effect on
IDE projects.  Any directories after the EXCLUDE_FROM_ALL marker will
not be included in the top level makefile or project file.  This is
useful for having CMake create makefiles or projects for a set of
examples in a project.  You would want CMake to generate makefiles or
project files for all the examples at the same time, but you would not
want them to show up in the top level project or be built each time
make is run from the top.

use_mangled_mesa
----------------

Disallowed.  See CMake Policy ``CMP0030``.

Copy mesa headers for use in combination with system GL.

::

 use_mangled_mesa(PATH_TO_MESA OUTPUT_DIRECTORY)

The path to mesa includes, should contain gl_mangle.h.  The mesa
headers are copied to the specified output directory.  This allows
mangled mesa headers to override other GL headers by being added to
the include directory path earlier.

utility_source
--------------

Disallowed.  See CMake Policy ``CMP0034``.

Specify the source tree of a third-party utility.

::

 utility_source(cache_entry executable_name
                path_to_source [file1 file2 ...])

When a third-party utility's source is included in the distribution,
this command specifies its location and name.  The cache entry will
not be set unless the path_to_source and all listed files exist.  It
is assumed that the source tree of the utility will have been built
before it is needed.

When cross compiling CMake will print a warning if a utility_source()
command is executed, because in many cases it is used to build an
executable which is executed later on.  This doesn't work when cross
compiling, since the executable can run only on their target platform.
So in this case the cache entry has to be adjusted manually so it
points to an executable which is runnable on the build host.

variable_requires
-----------------

Disallowed.  See CMake Policy ``CMP0035``.

Use the if() command instead.

Assert satisfaction of an option's required variables.

::

 variable_requires(TEST_VARIABLE RESULT_VARIABLE
                   REQUIRED_VARIABLE1
                   REQUIRED_VARIABLE2 ...)

The first argument (TEST_VARIABLE) is the name of the variable to be
tested, if that variable is false nothing else is done.  If
TEST_VARIABLE is true, then the next argument (RESULT_VARIABLE) is a
variable that is set to true if all the required variables are set.
The rest of the arguments are variables that must be true or not set
to NOTFOUND to avoid an error.  If any are not true, an error is
reported.

write_file
----------

Deprecated. Use the file(WRITE ) command instead.

::

 write_file(filename "message to write"... [APPEND])

The first argument is the file name, the rest of the arguments are
messages to write.  If the argument APPEND is specified, then the
message will be appended.

NOTE 1: file(WRITE ...  and file(APPEND ...  do exactly the same as
this one but add some more functionality.

NOTE 2: When using write_file the produced file cannot be used as an
input to CMake (CONFIGURE_FILE, source file ...) because it will lead
to an infinite loop.  Use configure_file if you want to generate input
files to CMake.

CTest Commands
==============

These commands are available only in ctest scripts.

ctest_build
-----------

Build the project.

::

 ctest_build([BUILD build_dir] [TARGET target] [RETURN_VALUE res]
             [APPEND][NUMBER_ERRORS val] [NUMBER_WARNINGS val])

Builds the given build directory and stores results in Build.xml.  If
no BUILD is given, the CTEST_BINARY_DIRECTORY variable is used.

The TARGET variable can be used to specify a build target.  If none is
specified, the "all" target will be built.

The RETURN_VALUE option specifies a variable in which to store the
return value of the native build tool.  The NUMBER_ERRORS and
NUMBER_WARNINGS options specify variables in which to store the number
of build errors and warnings detected.

The APPEND option marks results for append to those previously
submitted to a dashboard server since the last ctest_start.  Append
semantics are defined by the dashboard server in use.

ctest_configure
---------------

Configure the project build tree.

::

 ctest_configure([BUILD build_dir] [SOURCE source_dir] [APPEND]
                 [OPTIONS options] [RETURN_VALUE res])

Configures the given build directory and stores results in
Configure.xml.  If no BUILD is given, the CTEST_BINARY_DIRECTORY
variable is used.  If no SOURCE is given, the CTEST_SOURCE_DIRECTORY
variable is used.  The OPTIONS argument specifies command line
arguments to pass to the configuration tool.  The RETURN_VALUE option
specifies a variable in which to store the return value of the native
build tool.

The APPEND option marks results for append to those previously
submitted to a dashboard server since the last ctest_start.  Append
semantics are defined by the dashboard server in use.

ctest_coverage
--------------

Collect coverage tool results.

::

 ctest_coverage([BUILD build_dir] [RETURN_VALUE res] [APPEND]
                [LABELS label1 [label2 [...]]])

Perform the coverage of the given build directory and stores results
in Coverage.xml.  The second argument is a variable that will hold
value.

The LABELS option filters the coverage report to include only source
files labeled with at least one of the labels specified.

The APPEND option marks results for append to those previously
submitted to a dashboard server since the last ctest_start.  Append
semantics are defined by the dashboard server in use.

ctest_empty_binary_directory
----------------------------

empties the binary directory

::

 ctest_empty_binary_directory( directory )

Removes a binary directory.  This command will perform some checks
prior to deleting the directory in an attempt to avoid malicious or
accidental directory deletion.

ctest_memcheck
--------------

Run tests with a dynamic analysis tool.

::

 ctest_memcheck([BUILD build_dir] [RETURN_VALUE res] [APPEND]
            [START start number] [END end number]
            [STRIDE stride number] [EXCLUDE exclude regex ]
            [INCLUDE include regex]
            [EXCLUDE_LABEL exclude regex]
            [INCLUDE_LABEL label regex]
            [PARALLEL_LEVEL level] )

Tests the given build directory and stores results in MemCheck.xml.
The second argument is a variable that will hold value.  Optionally,
you can specify the starting test number START, the ending test number
END, the number of tests to skip between each test STRIDE, a regular
expression for tests to run INCLUDE, or a regular expression for tests
not to run EXCLUDE.  EXCLUDE_LABEL and INCLUDE_LABEL are regular
expressions for tests to be included or excluded by the test property
LABEL.  PARALLEL_LEVEL should be set to a positive number representing
the number of tests to be run in parallel.

The APPEND option marks results for append to those previously
submitted to a dashboard server since the last ctest_start.  Append
semantics are defined by the dashboard server in use.

ctest_read_custom_files
-----------------------

read CTestCustom files.

::

 ctest_read_custom_files( directory ... )

Read all the CTestCustom.ctest or CTestCustom.cmake files from the
given directory.

ctest_run_script
----------------

runs a ctest -S script

::

 ctest_run_script([NEW_PROCESS] script_file_name script_file_name1
             script_file_name2 ... [RETURN_VALUE var])

Runs a script or scripts much like if it was run from ctest -S.  If no
argument is provided then the current script is run using the current
settings of the variables.  If NEW_PROCESS is specified then each
script will be run in a separate process.If RETURN_VALUE is specified
the return value of the last script run will be put into var.

ctest_sleep
-----------

sleeps for some amount of time

::

 ctest_sleep(<seconds>)

Sleep for given number of seconds.

::

 ctest_sleep(<time1> <duration> <time2>)

Sleep for t=(time1 + duration - time2) seconds if t > 0.

ctest_start
-----------

Starts the testing for a given model

::

 ctest_start(Model [TRACK <track>] [APPEND] [source [binary]])

Starts the testing for a given model.  The command should be called
after the binary directory is initialized.  If the 'source' and
'binary' directory are not specified, it reads the
CTEST_SOURCE_DIRECTORY and CTEST_BINARY_DIRECTORY.  If the track is
specified, the submissions will go to the specified track.  If APPEND
is used, the existing TAG is used rather than creating a new one based
on the current time stamp.

ctest_submit
------------

Submit results to a dashboard server.

::

 ctest_submit([PARTS ...] [FILES ...] [RETRY_COUNT count]                [RETRY_DELAY delay][RETURN_VALUE res])

By default all available parts are submitted if no PARTS or FILES are
specified.  The PARTS option lists a subset of parts to be submitted.
Valid part names are:

::

 Start      = nothing
 Update     = ctest_update results, in Update.xml
 Configure  = ctest_configure results, in Configure.xml
 Build      = ctest_build results, in Build.xml
 Test       = ctest_test results, in Test.xml
 Coverage   = ctest_coverage results, in Coverage.xml
 MemCheck   = ctest_memcheck results, in DynamicAnalysis.xml
 Notes      = Files listed by CTEST_NOTES_FILES, in Notes.xml
 ExtraFiles = Files listed by CTEST_EXTRA_SUBMIT_FILES
 Upload     = Files prepared for upload by ctest_upload(), in Upload.xml
 Submit     = nothing

The FILES option explicitly lists specific files to be submitted.
Each individual file must exist at the time of the call.

The RETRY_DELAY option specifies how long in seconds to wait after a
timed-out submission before attempting to re-submit.

The RETRY_COUNT option specifies how many times to retry a timed-out
submission.

ctest_test
----------

Run tests in the project build tree.

::

 ctest_test([BUILD build_dir] [APPEND]
            [START start number] [END end number]
            [STRIDE stride number] [EXCLUDE exclude regex ]
            [INCLUDE include regex] [RETURN_VALUE res]
            [EXCLUDE_LABEL exclude regex]
            [INCLUDE_LABEL label regex]
            [PARALLEL_LEVEL level]
            [SCHEDULE_RANDOM on]
            [STOP_TIME time of day])

Tests the given build directory and stores results in Test.xml.  The
second argument is a variable that will hold value.  Optionally, you
can specify the starting test number START, the ending test number
END, the number of tests to skip between each test STRIDE, a regular
expression for tests to run INCLUDE, or a regular expression for tests
to not run EXCLUDE.  EXCLUDE_LABEL and INCLUDE_LABEL are regular
expression for test to be included or excluded by the test property
LABEL.  PARALLEL_LEVEL should be set to a positive number representing
the number of tests to be run in parallel.  SCHEDULE_RANDOM will
launch tests in a random order, and is typically used to detect
implicit test dependencies.  STOP_TIME is the time of day at which the
tests should all stop running.

The APPEND option marks results for append to those previously
submitted to a dashboard server since the last ctest_start.  Append
semantics are defined by the dashboard server in use.

ctest_update
------------

Update the work tree from version control.

::

 ctest_update([SOURCE source] [RETURN_VALUE res])

Updates the given source directory and stores results in Update.xml.
If no SOURCE is given, the CTEST_SOURCE_DIRECTORY variable is used.
The RETURN_VALUE option specifies a variable in which to store the
result, which is the number of files updated or -1 on error.

ctest_upload
------------

Upload files to a dashboard server.

::

 ctest_upload(FILES ...)

Pass a list of files to be sent along with the build results to the
dashboard server.