I'm developing a script that checks the version of some installed C programs. The version check is performed with the --version option. However, this option may not be implemented in all the checked programs. When the option is implemented I use:
version=$(./$program_name --version)
But when it's not, the program just starts executing. If I just execute the program in the background and the stop it if continues running, I can never get the version number. Is there a way to check whether the option is implemented without letting the program run?
If you are referring to any arbitrary C program, no there is currently no way to reliably check if a program supports an option. You can try guessing with a mixture of ./program --help, ./program --usage, ./program -h and ./program --this-option-is-a-lie-or-some-other-bogus-option-to-give-usage-information. However, it all ultimately boils down to guesswork.