GETPGID(P) POSIX Programmer's Manual GETPGID(P)
getpgid - get the process group ID for a process
pid_t getpgid(pid_t pid);
The getpgid() function shall return the process group ID of the process whose process ID
is equal to pid. If pid is equal to 0, getpgid() shall return the process group ID of the
Upon successful completion, getpgid() shall return a process group ID. Otherwise, it shall
return (pid_t)-1 and set errno to indicate the error.
The getpgid() function shall fail if:
EPERM The process whose process ID is equal to pid is not in the same session as the
calling process, and the implementation does not allow access to the process group
ID of that process from the calling process.
ESRCH There is no process with a process ID equal to pid.
The getpgid() function may fail if:
EINVAL The value of the pid argument is invalid.
The following sections are informative.
exec() , fork() , getpgrp() , getpid() , getsid() , setpgid() , setsid() , the Base Defi-
nitions volume of IEEE Std 1003.1-2001, <unistd.h>
Portions of this text are reprinted and reproduced in electronic form from IEEE Std
1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System
Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by
the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version and the original IEEE and The Open Group
Standard, the original IEEE and The Open Group Standard is the referee document. The orig-
inal Standard can be obtained online at http://www.opengroup.org/unix/online.html .
IEEE/The Open Group 2003 GETPGID(P)