C program under Linux: how to find out if another program is running

Question

My C program running under Linux wants to find out, by name, if another program is running. How to do it?

Answer 1

There are two ways basically:

• Use popen("pgrep yourproc", "r"); and then fgets from it
• Use opendir and readdir to parse /proc - this is basically what ps(1) does

Not the cleanest but I would go with the first of these.