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Config.in
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Config.in
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#
# For a description of the syntax of this configuration file,
# see extra/config/Kconfig-language.txt
#
mainmenu "uClibc $VERSION C Library Configuration"
config DESIRED_TARGET_ARCH
string
option env="ARCH"
config VERSION
string
option env="VERSION"
choice
prompt "Target Architecture"
default TARGET_alpha if DESIRED_TARGET_ARCH = "alpha"
default TARGET_arc if DESIRED_TARGET_ARCH = "arc"
default TARGET_arm if DESIRED_TARGET_ARCH = "arm"
default TARGET_avr32 if DESIRED_TARGET_ARCH = "avr32"
default TARGET_bfin if DESIRED_TARGET_ARCH = "bfin"
default TARGET_cris if DESIRED_TARGET_ARCH = "cris"
default TARGET_e1 if DESIRED_TARGET_ARCH = "e1"
default TARGET_frv if DESIRED_TARGET_ARCH = "frv"
default TARGET_h8300 if DESIRED_TARGET_ARCH = "h8300"
default TARGET_hppa if DESIRED_TARGET_ARCH = "hppa"
default TARGET_i386 if DESIRED_TARGET_ARCH = "i386"
default TARGET_i960 if DESIRED_TARGET_ARCH = "i960"
default TARGET_ia64 if DESIRED_TARGET_ARCH = "ia64"
default TARGET_m68k if DESIRED_TARGET_ARCH = "m68k"
default TARGET_metag if DESIRED_TARGET_ARCH = "metag"
default TARGET_microblaze if DESIRED_TARGET_ARCH = "microblaze"
default TARGET_mips if DESIRED_TARGET_ARCH = "mips"
default TARGET_nios if DESIRED_TARGET_ARCH = "nios"
default TARGET_nios2 if DESIRED_TARGET_ARCH = "nios2"
default TARGET_powerpc if DESIRED_TARGET_ARCH = "powerpc"
default TARGET_sh if DESIRED_TARGET_ARCH = "sh"
default TARGET_sh64 if DESIRED_TARGET_ARCH = "sh64"
default TARGET_sparc if DESIRED_TARGET_ARCH = "sparc"
default TARGET_v850 if DESIRED_TARGET_ARCH = "v850"
default TARGET_vax if DESIRED_TARGET_ARCH = "vax"
default TARGET_x86_64 if DESIRED_TARGET_ARCH = "x86_64"
default TARGET_xtensa if DESIRED_TARGET_ARCH = "xtensa"
help
The architecture of your target.
config TARGET_alpha
bool "alpha"
config TARGET_arc
bool "arc"
config TARGET_arm
bool "arm"
config TARGET_avr32
bool "avr32"
config TARGET_bfin
bool "bfin"
config TARGET_c6x
bool "c6x"
config TARGET_cris
bool "cris"
config TARGET_e1
bool "e1 (BROKEN)"
config TARGET_frv
bool "frv (BROKEN)"
config TARGET_h8300
bool "h8300"
config TARGET_hppa
bool "hppa"
config TARGET_i386
bool "i386"
config TARGET_i960
bool "i960 (BROKEN)"
config TARGET_ia64
bool "ia64"
config TARGET_m68k
bool "m68k"
config TARGET_metag
bool "metag"
config TARGET_microblaze
bool "microblaze"
config TARGET_mips
bool "mips"
config TARGET_nios
bool "nios"
config TARGET_nios2
bool "nios2"
config TARGET_powerpc
bool "powerpc"
config TARGET_sh
bool "superh"
config TARGET_sh64
bool "sh64"
config TARGET_sparc
bool "sparc"
config TARGET_v850
bool "v850 (BROKEN)"
config TARGET_vax
bool "vax"
config TARGET_x86_64
bool "x86_64"
config TARGET_xtensa
bool "xtensa"
endchoice
menu "Target Architecture Features and Options"
if TARGET_alpha
source "extra/Configs/Config.alpha"
endif
if TARGET_arm
source "extra/Configs/Config.arm"
endif
if TARGET_avr32
source "extra/Configs/Config.avr32"
endif
if TARGET_bfin
source "extra/Configs/Config.bfin"
endif
if TARGET_cris
source "extra/Configs/Config.cris"
endif
if TARGET_e1
source "extra/Configs/Config.e1"
endif
if TARGET_frv
source "extra/Configs/Config.frv"
endif
if TARGET_h8300
source "extra/Configs/Config.h8300"
endif
if TARGET_hppa
source "extra/Configs/Config.hppa"
endif
if TARGET_i386
source "extra/Configs/Config.i386"
endif
if TARGET_i960
source "extra/Configs/Config.i960"
endif
if TARGET_ia64
source "extra/Configs/Config.ia64"
endif
if TARGET_m68k
source "extra/Configs/Config.m68k"
endif
if TARGET_metag
source "extra/Configs/Config.metag"
endif
if TARGET_nios
source "extra/Configs/Config.nios"
endif
if TARGET_nios2
source "extra/Configs/Config.nios2"
endif
if TARGET_microblaze
source "extra/Configs/Config.microblaze"
endif
if TARGET_mips
source "extra/Configs/Config.mips"
endif
if TARGET_powerpc
source "extra/Configs/Config.powerpc"
endif
if TARGET_sh
source "extra/Configs/Config.sh"
endif
if TARGET_sh64
source "extra/Configs/Config.sh64"
endif
if TARGET_sparc
source "extra/Configs/Config.sparc"
endif
if TARGET_v850
source "extra/Configs/Config.v850"
endif
if TARGET_vax
source "extra/Configs/Config.vax"
endif
if TARGET_x86_64
source "extra/Configs/Config.x86_64"
endif
if TARGET_xtensa
source "extra/Configs/Config.xtensa"
endif
if TARGET_c6x
source "extra/Configs/Config.c6x"
endif
if TARGET_arc
source "extra/Configs/Config.arc"
endif
config TARGET_SUBARCH
string
default "e500" if CONFIG_E500
default "classic" if CONFIG_CLASSIC
default "sh4" if CONFIG_SH4
default "" if CONFIG_386
default "i486" if CONFIG_486
default "i586" if CONFIG_586
default "i686" if CONFIG_686
default "arcv2" if CONFIG_ARC_CPU_HS
default ""
source "extra/Configs/Config.in.arch"
endmenu
menu "General Library Settings"
config HAVE_NO_PIC
bool
config DOPIC
bool "Generate only Position Independent Code (PIC)"
default y
depends on !HAVE_NO_PIC
help
If you wish to build all of uClibc as PIC objects, then answer Y here.
If you are unsure, then you should answer N.
config ARCH_HAS_NO_SHARED
bool
config ARCH_HAS_NO_LDSO
bool
select ARCH_HAS_NO_SHARED
config ARCH_HAS_UCONTEXT
bool
config HAVE_SHARED
bool "Enable shared libraries"
depends on !ARCH_HAS_NO_SHARED
default y
help
If you wish to build uClibc with support for shared libraries then
answer Y here. If you only want to build uClibc as a static library,
then answer N.
config FORCE_SHAREABLE_TEXT_SEGMENTS
bool "Only load shared libraries which can share their text segment"
depends on HAVE_SHARED
select DOPIC
help
If you answer Y here, the uClibc native shared library loader will
only load shared libraries, which do not need to modify any
non-writable segments. These libraries haven't set the DT_TEXTREL
tag in the dynamic section (==> objdump).
All your libraries must be compiled with -fPIC or -fpic, and all
assembler function must be written as position independent code (PIC).
Enabling this option will make uClibc's shared library loader a
little bit smaller and guarantee that no memory will be wasted by
badly coded shared libraries.
config LDSO_LDD_SUPPORT
bool "Native 'ldd' support"
depends on HAVE_SHARED
default y
help
Enable all the code needed to support traditional ldd,
which executes the shared library loader to resolve all dependencies
and then provide a list of shared libraries that are required for an
application to function. Disabling this option will make uClibc's
shared library loader a little bit smaller.
Most people will answer Y.
config LDSO_CACHE_SUPPORT
bool "Enable library loader cache (ld.so.conf)"
depends on HAVE_SHARED
default y
help
Enable this to make use of /etc/ld.so.conf, the shared library loader
cache configuration file to support for non-standard library paths.
After updating this file, it is necessary to run 'ldconfig' to update
the /etc/ld.so.cache shared library loader cache file.
config LDSO_PRELOAD_ENV_SUPPORT
bool "Enable library loader LD_PRELOAD environment"
depends on HAVE_SHARED
default y
help
Enable this to make use of LD_PRELOAD environment variable.
A whitespace-separated list of additional, user-specified, ELF shared
libraries to be loaded before all others. This can be used to
selectively override functions in other shared libraries. For
set-user-ID/set-group-ID ELF binaries, only libraries in the standard
search directories that are also set-user-ID will be loaded.
config LDSO_PRELOAD_FILE_SUPPORT
bool "Enable library loader preload file (ld.so.preload)"
depends on HAVE_SHARED
help
Enable this to make use of /etc/ld.so.preload. This file contains a
whitespace separated list of shared libraries to be loaded before
the program.
config LDSO_BASE_FILENAME
string "Shared library loader naming prefix"
depends on HAVE_SHARED && (LDSO_CACHE_SUPPORT || LDSO_PRELOAD_FILE_SUPPORT)
default "ld.so"
help
If you wish to support both uClibc and glibc on the same system, it
is necessary to set this to something other than "ld.so" to avoid
conflicts with glibc, which also uses "ld.so". This prevents both
libraries from using the same /etc/ld.so.* files. If you wish to
support both uClibc and glibc on the same system then you should set
this to "ld-uClibc.so".
Most people will leave this set to the default of "ld.so".
WARNING: Changing the default prefix could cause problems with
binutils' ld !
config LDSO_STANDALONE_SUPPORT
bool "Dynamic linker stand-alone mode support"
depends on HAVE_SHARED
help
The dynamic linker can be run either indirectly through running some
dynamically linked program or library (in which case no command line
options to the dynamic linker can be passed and, in the ELF case, the
dynamic linker which is stored in the .interp section of the program
is executed) or directly by running:
/lib/ld-uClibc.so.* [OPTIONS] [PROGRAM [ARGUMENTS]]
Stand-alone execution is a prerequisite for adding prelink
capabilities to uClibc dynamic linker, as well useful for testing an
updated version of the dynamic linker without breaking the system.
config LDSO_PRELINK_SUPPORT
bool "Dynamic linker prelink support"
depends on HAVE_SHARED
select LDSO_STANDALONE_SUPPORT
help
The dynamic linker can be used in stand-alone mode by the prelink tool
for prelinking ELF shared libraries and binaries to speed up startup
time. It also is able to load and handle prelinked libraries and
binaries at runtime.
config UCLIBC_STATIC_LDCONFIG
bool "Link ldconfig statically"
depends on HAVE_SHARED
default y
help
Enable this option to statically link the ldconfig binary.
Making ldconfig static can be beneficial if you have a library
problem and need to use ldconfig to recover. Sometimes it is
preferable to instead keep the size of the system down, in which
case you should disable this option.
config LDSO_RUNPATH
bool "Enable ELF RUNPATH tag support"
depends on HAVE_SHARED
default y if LDSO_CACHE_SUPPORT
help
ELF's may have dynamic RPATH/RUNPATH tags. These tags list paths
which extend the library search paths. They are really only useful
if a package installs libraries in non standard locations and
ld.so.conf support is disabled.
Usage of RUNPATH tags is not too common, so disabling this feature
should be safe for most people.
config LDSO_RUNPATH_OF_EXECUTABLE
bool "Use executables RUNPATH/RPATH when searching for libraries."
depends on LDSO_RUNPATH
default n
help
Use the executables RUNPATH/RPATH to find to find libraries even
though this behavour is not standard. Setting this option causes
the uclibc dynamic linker behavour to match the glibc dynamic linker.
config LDSO_SAFE_RUNPATH
bool "Allow only RUNPATH beginning with /"
depends on LDSO_RUNPATH
default y
help
Allow only absolute path in RPATH/RUNPATH.
config LDSO_SEARCH_INTERP_PATH
bool "Add ldso path to lib search path"
depends on HAVE_SHARED
default y
help
The ldso is told where it is being executed from and can use that
path to find related core libraries. This is useful by default,
but can be annoying in a mixed development environment.
i.e. if the ldso is run from /foo/boo/ldso.so, it will start its
library search with /foo/boo/
If unsure, simply say Y here.
config LDSO_LD_LIBRARY_PATH
bool "Add LD_LIBRARY_PATH to lib search path"
depends on HAVE_SHARED
default y
help
On hardened system it could be useful to disable the use of
LD_LIBRARY_PATH environment variable (a colon-separated list of
directories in which to search for ELF libraries at execution-time).
If unsure, simply say Y here.
config LDSO_NO_CLEANUP
bool "Disable automatic unloading of dynamically loaded shared objects"
depends on HAVE_SHARED
help
If you need complete allocation traces when debugging memory leaks
using Valgrind in a process that dynamically loads shared objects,
then answer Y here. Unlike glibc, uClibc unloads all dynamically
loaded shared objects when a process exits, which prevents Valgrind
from correctly resolving the symbols from the unloaded shared objects.
Unless you know you need this, you should answer N.
config UCLIBC_CTOR_DTOR
bool "Support global constructors and destructors"
default y
help
If you wish to build uClibc with support for global constructor
(ctor) and global destructor (dtor) support, then answer Y here.
When ctor/dtor support is enabled, binaries linked with uClibc must
also be linked with crtbegin.o and crtend.o which are provided by gcc
(the "*startfile:" and "*endfile:" settings in your gcc specs file
may need to be adjusted to include these files). This support will
also add a small amount of additional size to each binary compiled vs
uClibc. If you will be using uClibc with C++, or if you need the gcc
__attribute__((constructor)) and __attribute__((destructor)) to work,
then you definitely want to answer Y here. If you don't need ctors
or dtors and want your binaries to be as small as possible, then
answer N.
config LDSO_GNU_HASH_SUPPORT
bool "Enable GNU hash style support"
depends on HAVE_SHARED
help
Newest binutils support a new hash style named GNU-hash. The dynamic
linker will use the new GNU-hash section (.gnu.hash) for symbol lookup
if present into the ELF binaries, otherwise it will use the old SysV
hash style (.hash). This ensures that it is completely backward
compatible.
Further, being the hash table implementation self-contained into each
executable and shared libraries, objects with mixed hash style can
peacefully coexist in the same process.
If you want to use this new feature, answer Y
choice
prompt "Thread support"
#default UCLIBC_HAS_THREADS_NATIVE if (TARGET_alpha || TARGET_arm || TARGET_i386 || TARGET_mips || TARGET_powerpc || TARGET_sh || TARGET_sh64)
default HAS_NO_THREADS
help
If you want to compile uClibc with pthread support, then answer Y.
This will increase the size of uClibc by adding a bunch of locking
to critical data structures, and adding extra code to ensure that
functions are properly reentrant.
config HAS_NO_THREADS
bool "none"
help
Disable thread support.
config LINUXTHREADS_OLD
bool "older (stable) version of linuxthreads"
# linuxthreads and linuxthreads.old need nanosleep()
select UCLIBC_HAS_REALTIME
help
There are two versions of linuxthreads. The older (stable) version
has been in uClibc for quite a long time but hasn't seen too many
updates other than bugfixes.
config LINUXTHREADS_NEW
bool "slightly newer version of linuxthreads"
depends on ARCH_HAS_DEPRECATED_SYSCALLS
help
The new version has not been tested much, and lacks ports for arches
which glibc does not support (like bfin/frv/etc...), but is based on
the latest code from glibc, so it may be the only choice for the
newer ports (like alpha/amd64/64bit arches and hppa).
config UCLIBC_HAS_THREADS_NATIVE
bool "Native POSIX Threading (NPTL)"
select UCLIBC_HAS_TLS
select UCLIBC_HAS_STDIO_FUTEXES
select UCLIBC_HAS_REALTIME
# i386 has no lowlevellock support (yet) as opposed to i486 onward
depends on !CONFIG_386
help
If you want to compile uClibc with NPTL support, then answer Y.
IMPORTANT NOTE! NPTL requires a Linux 2.6 kernel, binutils
at least version 2.16 and GCC with at least version 4.1.0. NPTL
will not work with older versions of any above sources. If you
ignore any of these guidelines, you do so at your own risk. Do
not ask for help on any of the development mailing lists.
!!!! WARNING !!!! BIG FAT WARNING !!!! REALLY BIG FAT WARNING !!!!
This is experimental code and at times it may not even build and
even if it does it might decide to do random damage. This code is
potentially hazardous to your health and sanity. It will remain
that way until further notice at which point this notice will
disappear. Thank you for your support and for not smoking.
endchoice
config UCLIBC_HAS_THREADS
def_bool y if !HAS_NO_THREADS
config UCLIBC_HAS_TLS
bool "Thread-Local Storage"
depends on UCLIBC_HAS_THREADS_NATIVE
help
If you want to enable TLS support then answer Y.
This is fast an efficient way to store per-thread local data
which is not on stack. It needs __thread support enabled in
gcc.
config PTHREADS_DEBUG_SUPPORT
bool "Build pthreads debugging support"
depends on UCLIBC_HAS_THREADS
help
Say Y here if you wish to be able to debug applications that use
uClibc's pthreads library. By enabling this option, a library
named libthread_db will be built. This library will be dlopen()'d
by gdb and will allow gdb to debug the threads in your application.
IMPORTANT NOTE! Because gdb must dlopen() the libthread_db library,
you must compile gdb with uClibc in order for pthread debugging to
work properly.
If you are doing development and want to debug applications using
uClibc's pthread library, answer Y. Otherwise, answer N.
config UCLIBC_HAS_SYSLOG
bool "Syslog support"
default y
depends on UCLIBC_HAS_NETWORK_SUPPORT
select UCLIBC_HAS_SOCKET
help
Support sending messages to the system logger.
This requires socket-support.
config UCLIBC_HAS_LFS
bool "Large File Support"
default y
help
If you wish to build uClibc with support for accessing large files
(i.e. files greater then 2 GiB) then answer Y. Do not enable this
if you are using an older Linux kernel (2.0.x) that lacks large file
support. Enabling this option will increase the size of uClibc.
choice
prompt "Malloc Implementation"
default MALLOC if ! ARCH_USE_MMU
default MALLOC_STANDARD if ARCH_USE_MMU
config MALLOC
bool "malloc"
help
"malloc" use mmap for all allocations and so works very well on
MMU-less systems that do not support the brk() system call. It is
pretty smart about reusing already allocated memory, and minimizing
memory wastage.
This is the default for uClinux MMU-less systems.
config MALLOC_SIMPLE
bool "malloc-simple"
help
"malloc-simple" is trivially simple and slow as molasses. It
was written from scratch for uClibc, and is the simplest possible
(and therefore smallest) malloc implementation.
This uses only the mmap() system call to allocate and free memory,
and does not use the brk() system call at all, making it a fine
choice for MMU-less systems with very limited memory. It's 100%
standards compliant, thread safe, very small, and releases freed
memory back to the OS immediately rather than keeping it in the
process's heap for reallocation. It is also VERY SLOW.
config MALLOC_STANDARD
bool "malloc-standard"
depends on ARCH_USE_MMU
help
"malloc-standard" is derived from the public domain dlmalloc
implementation by Doug Lea. It is quite fast, and is pretty smart
about reusing already allocated memory, and minimizing memory
wastage. This uses brk() for small allocations, while using mmap()
for larger allocations. This is the default malloc implementation
for uClibc.
If unsure, answer "malloc-standard".
endchoice
config MALLOC_GLIBC_COMPAT
bool "Malloc returns live pointer for malloc(0)"
help
The behavior of malloc(0) is listed as implementation-defined by
SuSv3. Glibc returns a valid pointer to something, while uClibc
normally returns NULL. I personally feel glibc's behavior is
not particularly safe, and allows buggy applications to hide very
serious problems.
When this option is enabled, uClibc will act just like glibc, and
return a live pointer when someone calls malloc(0). This pointer
provides a malloc'ed area with a size of 1 byte. This feature is
mostly useful when dealing with applications using autoconf's broken
AC_FUNC_MALLOC macro (which redefines malloc as rpl_malloc if it
does not detect glibc style returning-a-valid-pointer-for-malloc(0)
behavior). Most people can safely answer N.
config UCLIBC_HAS_OBSTACK
bool "Obstack Support (gnu extension)"
help
When this option is enabled, uClibc will provide support for obstacks.
An obstack is a structure in which memory can be dynamically allocated
as a 'stack of objects'. Many programs need this GNU extention and
you should say Y if you are using any. Otherwise, say N to save some
space.
config UCLIBC_DYNAMIC_ATEXIT
bool "Dynamic atexit() Support"
default y
help
When this option is enabled, uClibc will support an infinite number,
of atexit() and on_exit() functions, limited only by your available
memory. This can be important when uClibc is used with C++, since
global destructors are implemented via atexit(), and it is quite
possible to exceed the default number when this option is disabled.
Enabling this option adds a few bytes, and more significantly makes
atexit and on_exit depend on malloc, which can be bad when compiling
static executables.
Unless you use uClibc with C++, you should probably answer N.
config COMPAT_ATEXIT
bool "Old (visible) atexit Support"
help
Enable this option if you want to update from 0.9.28 to git/0.9.29,
else you will be missing atexit() until you rebuild all apps.
config UCLIBC_HAS_UTMPX
bool "utmpx based support for tracking login/logouts to/from the system"
help
Answer y to enable support for accessing user accounting database.
It can be used to track all login/logout to the system.
config UCLIBC_HAS_UTMP
bool "utmp support (XPG2 compat, SVr4 compat)"
depends on UCLIBC_HAS_UTMPX
help
Answer y to enable legacy SVID support for accessing
user accounting database:
getutent(), getutid(), getutline(), pututline(),
setutent(), endutent(), utmpname() in utmp.h
It can be used to track all login/logout to the system.
If unsure, answer N and use corresponding POSIX functions
from utmpx.h
config UCLIBC_SUSV2_LEGACY
bool "Enable SuSv2 LEGACY functions"
help
Enable this option if you want to have SuSv2 LEGACY functions
Currently applies to:
valloc
WARNING! ABI incompatibility.
config UCLIBC_SUSV3_LEGACY
bool "Enable SuSv3 LEGACY functions"
#vfork,
# h_errno
# gethostbyaddr
# gethostbyname
help
Enable this option if you want to have SuSv3 LEGACY functions
in the library, else they are replaced by SuSv3 proposed macros.
Currently applies to:
bcmp, bcopy, bzero, index, rindex, ftime,
bsd_signal, (ecvt), (fcvt), gcvt, (getcontext),
(getwd), (makecontext),
mktemp, (pthread_attr_getstackaddr), (pthread_attr_setstackaddr),
scalb, (setcontext), (swapcontext), ualarm, usleep,
wcswcs.
WARNING! ABI incompatibility.
config UCLIBC_HAS_CONTEXT_FUNCS
bool "Use obsolescent context control functions"
depends on UCLIBC_SUSV3_LEGACY && ARCH_HAS_UCONTEXT
help
Add into library the SuSv3 obsolescent functions used for context
control. The setcontext family allows the implementation in C of
advanced control flow patterns such as iterators, fibers, and
coroutines. They may be viewed as an advanced version of
setjmp/longjmp; whereas the latter allows only a single non-local jump
up the stack, setcontext allows the creation of multiple cooperative
threads of control, each with its own stack.
These functions are: setcontext, getcontext, makecontext, swapcontext.
config UCLIBC_SUSV3_LEGACY_MACROS
bool "Enable SuSv3 LEGACY macros"
help
Enable this option if you want to have SuSv3 LEGACY macros.
Currently applies to bcopy/bzero/bcmp/index/rindex et al.
WARNING! ABI incompatibility.
config UCLIBC_SUSV4_LEGACY
bool "Enable SuSv4 LEGACY or obsolescent functions"
help
Enable this option if you want to have SuSv4 LEGACY functions
and macros in the library.
Currently applies to:
- XSI functions:
_longjmp, _setjmp, _tolower, _toupper, ftw, getitimer,
gettimeofday, isascii, pthread_getconcurrency,
pthread_setconcurrency, setitimer, setpgrp, sighold,
sigignore, sigpause, sigrelse, sigset, siginterrupt,
tempnam, toascii, ulimit.
- Base functions:
asctime, asctime_r, ctime, ctime_r, gets, rand_r,
tmpnam, utime.
WARNING! ABI incompatibility.
config UCLIBC_STRICT_HEADERS
bool "Hide structures and constants for unsupported features"
help
Hide structures and constants in headers that should not be used,
because the respective feature is disabled.
WARNING! enabling this option requires to patch many faulty apps,
since they make (wrongly) use of these structures/constants,
although the feature was disabled.
config UCLIBC_HAS_STUBS
bool "Provide stubs for unavailable functionality"
help
With this option uClibc provides non-functional stubs for
functions which are impossible to implement on the target
architecture. Otherwise, such functions are simply omitted.
config UCLIBC_HAS_SHADOW
bool "Shadow Password Support"
default y
help
Answer N if you do not need shadow password support.
Most people will answer Y.
config UCLIBC_HAS_PROGRAM_INVOCATION_NAME
bool "Support for program_invocation_name"
help
Support for the GNU-specific program_invocation_name and
program_invocation_short_name strings. Some GNU packages
(like tar and coreutils) utilize these for extra useful
output, but in general are not required.
At startup, these external strings are automatically set
up based on the value of ARGV[0].
If unsure, just answer N.
config UCLIBC_HAS___PROGNAME
bool "Support for __progname"
default y
help
Some packages (like openssh) like to peek into internal libc
symbols to make their output a bit more user friendly.
At startup, __progname is automatically set up based on the
value of ARGV[0].
If unsure, just answer N.
config UCLIBC_HAS_PTY
bool "Support for pseudo-terminals"
default y
help
This enables support for pseudo-terminals (see man 4 pts
and man 7 pty).
If unsure, just answer Y.
config ASSUME_DEVPTS
bool "Assume that /dev/pts is a devpts or devfs file system"
default y
depends on UCLIBC_HAS_PTY
help
Enable this if /dev/pts is on a devpts or devfs filesystem. Both
these filesystems automatically manage permissions on the /dev/pts
devices. You may need to mount your devpts or devfs filesystem on
/dev/pts for this to work.
Most people should answer Y.
config UNIX98PTY_ONLY
bool "Support only Unix 98 PTYs"
default y
depends on UCLIBC_HAS_PTY
help
If you want to support only Unix 98 PTYs enable this. Some older
applications may need this disabled and will thus use legacy BSD
style PTY handling which is more complex and also bigger than
Unix 98 PTY handling.
For most current programs, you can generally answer Y.
if UNIX98PTY_ONLY
config UCLIBC_HAS_GETPT
bool "Support getpt() (glibc-compat)"
depends on UCLIBC_HAS_PTY
help
Some packages may need getpt().
All of those are non-standard and can be considered
GNU/libc compatibility.
Either use posix_openpt() or just open /dev/ptmx yourself.
If unsure, just say N.
endif
if !UNIX98PTY_ONLY
# Have to use __libc_ptyname{1,2}[] and related bloat
config UCLIBC_HAS_GETPT
def_bool y
endif
config UCLIBC_HAS_LIBUTIL
bool "Provide libutil library and functions"
depends on UCLIBC_HAS_PTY
help
Provide a libutil library.
This non-standard conforming library provides the following
utility functions:
forkpty(): combines openpty(), fork(2), and login_tty() to
create a new process operating in a pseudo-terminal.
login(): write utmp and wtmp entries
login_tty(): prepares for a login on the tty fd by creating a
new session, making fd the controlling terminal for
the calling process, setting fd to be the standard
input, output, and error streams of the current
process, and closing fd.
logout(): write utmp and wtmp entries
logwtmp(): constructs a utmp structure and calls updwtmp() to
append the structure to the utmp file.
openpty(): finds an available pseudo-terminal and returns
file descriptors for the master and slave
This library adds about 3k-4k to your system.
config UCLIBC_HAS_TM_EXTENSIONS
bool "Support 'struct tm' timezone extension fields"
default y
help
Enabling this option adds fields to 'struct tm' in time.h for
tracking the number of seconds east of UTC, and an abbreviation for
the current timezone. These fields are not specified by the SuSv3
standard, but they are commonly used in both GNU and BSD application
code.
To strictly follow the SuSv3 standard, leave this disabled.
Most people will probably want to answer Y.
config UCLIBC_HAS_TZ_CACHING
bool "Enable caching of the last valid timezone 'TZ' string"
default y
help
Answer Y to enable caching of the last valid 'TZ' string describing
the timezone setting. This allows a quick string compare to avoid
repeated parsing of unchanged 'TZ' strings when tzset() is called.
Most people will answer Y.
config UCLIBC_HAS_TZ_FILE
bool "Enable '/etc/TZ' file support to set a default timezone (uClibc-specific)"
default y
help
Answer Y to enable the setting of a default timezone for uClibc.
Ordinarily, uClibc gets the timezone information exclusively from the
'TZ' environment variable. In particular, there is no support for
the zoneinfo directory tree or the /etc/timezone file used by glibc.
With this option enabled, uClibc will use the value stored in the
file '/etc/TZ' (default path) to obtain timezone information if the
'TZ' environment variable is missing or has an invalid value. The
file consists of a single line (newline required) of text describing
the timezone in the format specified for the TZ environment variable.
Doing 'echo CST6CDT > /etc/TZ' is enough to create a valid file.
See
http://www.opengroup.org/onlinepubs/007904975/basedefs/xbd_chap08.html
for details on valid settings of 'TZ'.
Most people will answer Y.
config UCLIBC_HAS_TZ_FILE_READ_MANY
bool "Repeatedly read the '/etc/TZ' file"
depends on UCLIBC_HAS_TZ_FILE
default y
help
Answer Y to enable repeated reading of the '/etc/TZ' file even after
a valid value has been read. This incurs the overhead of an
open/read/close for each tzset() call (explicit or implied). However,
setting this will allow applications to update their timezone
information if the contents of the file change.
Most people will answer Y.
config UCLIBC_TZ_FILE_PATH
string "Path to the 'TZ' file for setting the global timezone"
depends on UCLIBC_HAS_TZ_FILE
default "/etc/TZ"
help
This is the path to the 'TZ' file.
Most people will use the default of '/etc/TZ'.
config UCLIBC_FALLBACK_TO_ETC_LOCALTIME
bool "Use /etc/localtime as a fallback"
depends on UCLIBC_HAS_TZ_FILE
default y
help
Answer Y to try to use /etc/localtime file.
On glibc systems this file (if it is in TZif2 format)
contains timezone string at the end.
Most people will answer Y.
endmenu
menu "Advanced Library Settings"
config UCLIBC_PWD_BUFFER_SIZE