valecs/unchanged

USAGE

unchanged - waits until file(s) change.
Usage: unchanged FILE [FILES...]
  Waits until the inotify kernel facility indicates one of FILE changed.
  Exit Status: index of changed file in argument list (starts with 1).


BUILDING

Simple invocation of

$ make clean all

should be sufficient to build. Copy ./bin/unchanged to somewhere in your path to
use.


DESCRIPTION

Unchanged makes it easy to add inotify(7) functionality to a script. This is
useful any time one wants to execute something whenever a file changes. For
instance, this project is built with every modification to a source file as
follows:

$ while ! unchanged $(make echo); do make; done;

The echo target in the make file outputs a list of sources, which unchanged then
monitors for changes. Unchanged exits with non-zero status when a file
changes. The exit code is the 1-indexed position of the first changed file in
the argument list.


IDEAS

* Support verbose output via an environmental variable
* Use exit code 0 to indicate change via environmental variable

BUGS

* If you monitor more than 255 files simultaneously, exit codes will wrap.