cpopenstderr

c popen won't catch stderr


I'm trying to use popen() to catch the stderr of a call, but of course it doesn't seem to be doing that. Any ideas?

My code looks more or less like this:

popen("nedit", "r");

But I'm getting all this garbage about non-utf8 on my screen...


Solution

  • popen gives you a file handle on a process' stdout, not its stderr. Its first argument is interpreted as a shell command, so you can do redirections in it:

    FILE *p = popen("prog 2>&1", "r");
    

    or, if you don't want the stdout at all,

    FILE *p = popen("prog 2>&1 >/dev/null", "r");
    

    (Any other file besides /dev/null is acceptable as well.)