How to embed version information into shared library and binary?

Question

On Linux, is there a way to embed version information into an ELF binary? I would like to embed this info at compile time so it can then be extract it using a script later.

Answer 1

To extend the @sashang answer, while avoiding the "$Id:$" issues mentioned by @cdunn2001, ...

You can add a file "version_info.h" to your project that has only:

#define VERSION_MAJOR "1"
#define VERSION_MINOR "0"
#define VERSION_PATCH "0"
#define VERSION_BUILD "0"

And in your main.c file have the line:

static char version[] = VERSION_MAJOR "." VERSION_MINOR "." VERSION_PATCH "." VERSION_BUILD;
static char timestamp[] = __DATE__ " " __TIME__;

(or however you want to use these values in your program)

Then set up a pre-build step which reads the version_info.h file, bumps the numbers appropriately, and writes it back out again. A daily build would just bump the VERSION_BUILD number, while a more serious release would bump other numbers.

If your makefile lists this on your object's prerequisite list, then the build will recompile what it needs to.