getpgid Subroutine

Purpose

Returns the process group ID of the calling process.

Library

Standard C Library (libc.a)

Syntax

#include <unistd.h>

pid_t getpgid (Pid)
(pid_ Pid)

Description

The getpgid subroutine returns the process group ID of the process whose process ID is equal to that specified by the Pid parameter. If the value of the Pid parameter is equal to (pid_t)0, the getpgid subroutine returns the process group ID of the calling process.

Parameter

Item	Description
Pid	The process ID of the process to return the process group ID for.

Return Values

Item	Description
id	The process group ID of the requested process
-1	Not successful and errno set to one of the following.

Error Code

Item	Description
ESRCH	There is no process with a process ID equal to Pid.

Item	Description
EPERM	The process whose process ID is equal to Pid is not in the same session as the calling process.
EINVAL	The value of the Pid argument is invalid.