NAME
getpgrp —
get process group
SYNOPSIS
#include
<unistd.h>
pid_t
getpgrp(void);
DESCRIPTION
The process group of the current process is returned bygetpgrp().
Process groups are used for distribution of signals, and by terminals to arbitrate requests for their input: processes that have the same process group as the terminal are foreground and may read, while others will block with a signal if they attempt to read.
This call is thus used by programs such as
csh(1) to create process groups in implementing job control. The
tcgetpgrp()
and
tcsetpgrp()
calls are used to get/set the process group of the control terminal.
SEE ALSO
HISTORY
The getpgrp function call appeared in
4.0BSD.
STANDARDS
The getpgrp() function conforms to IEEE
Std 1003.1-1988 (“POSIX”).
COMPATABILITY
This version of getpgrp() differs from
past Berkeley versions by not taking a pid_t pid
argument. This incompatibility is required by IEEE Std
1003.1-1988 (“POSIX.1”).
From the IEEE Std 1003.1-1988 (“POSIX.1”) Rationale:
4.3BSD provides a
getpgrp()
function that returns the process group ID for a specified process. Although
this function is used to support job control, all known job-control shells
always specify the calling process with this function. Thus, the simpler
System V getpgrp() suffices, and the added
complexity of the 4.3BSD getpgrp() has been omitted
from POSIX.1.