unix command result to a variable - char*

Question

How can I assign "pwd" (or any other command in that case) result (present working dir) to a variable which is char*?

command can be anything. Not bounded to just "pwd".

Thanks.

Answer 1

Start with popen. That will let you run a command with its standard output directed to a FILE * that your parent can read. From there it's just a matter of reading its output like you would any normal file (e.g., with fgets, getchar, etc.)

Generally, however, you'd prefer to avoid running an external program for that -- you should have getcwd available, which will give the same result much more directly.

Answer 2

Why not just call getcwd()? It's not part of C's standard library, but it is POSIX, and it's very widely supported.

Anyway, if pwd was just an example, have a look at popen(). That will run an external command and give you a FILE* with which to read its output.