How do I get the directory that a program is running from?

Question

Is there a platform-agnostic and filesystem-agnostic method to obtain the full path of the directory from where a program is running using C/C++? Not to be confused with the

Answer 1

The linux bash command which progname will report a path to program.

Even if one could issue the which command from within your program and direct the output to a tmp file and the program subsequently reads that tmp file, it will not tell you if that program is the one executing. It only tells you where a program having that name is located.

What is required is to obtain your process id number, and to parse out the path to the name

In my program I want to know if the program was executed from the user's bin directory or from another in the path or from /usr/bin. /usr/bin would contain the supported version. My feeling is that in Linux there is the one solution that is portable.