explain_getpgid_or_die - get process group and report errors

       libexplain version 1.4
       Copyright (C) 2011 Peter Miller

                                                                                       explain_getpgid_or_die(3)

       The explain_getpgid_or_die function is used to call the getpgid(2) system call. On failure an explanation
       will be printed to stderr, obtained from the explain_getpgid(3) function, and then the process terminates
       by calling exit(EXIT_FAILURE).

       The  explain_getpgid_on_error  function  is  used  to  call  the  getpgid(2)  system  call. On failure an
       explanation will be printed to stderr, obtained from the explain_getpgid(3) function, but  still  returns
       to the caller.

       pid     The pid, exactly as to be passed to the getpgid(2) system call.

       The explain_getpgid_or_die function is intended to be used in a fashion similar to the following example:
              pid_t result = explain_getpgid_or_die(pid);

       explain_getpgid_or_die - get process group and report errors

       The  explain_getpgid_or_die  function  only  returns  on success, see getpgid(2) for more information. On
       failure, prints an explanation and exits, it does not return.

       The explain_getpgid_on_error function always returns the value return by the  wrapped  getpgid(2)  system
       call.

getpgid(2)
               get process group

       explain_getpgid(3)
               explain getpgid(2) errors

       exit(2) terminate the calling process

       #include <libexplain/getpgid.h>
       pid_t explain_getpgid_or_die(pid_t pid);
       pid_t explain_getpgid_on_error(pid_t pid);