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PROLOG
This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface
may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface
may not be implemented on Linux.
NAME
setpgrp — set the process group ID
SYNOPSIS
#include <unistd.h>
pid_t setpgrp(void);
DESCRIPTION
If the calling process is not already a session leader, setpgrp() sets the process group ID of the
calling process to the process ID of the calling process. If setpgrp() creates a new session, then the
new session has no controlling terminal.
The setpgrp() function has no effect when the calling process is a session leader.
RETURN VALUE
Upon completion, setpgrp() shall return the process group ID.
ERRORS
No errors are defined.
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
It is unspecified whether this function behaves as setpgid(0,0) or setsid() unless the process is already
a session leader. Therefore, applications are encouraged to use setpgid() or setsid() as appropriate.
RATIONALE
None.
FUTURE DIRECTIONS
The setpgrp() function may be removed in a future version.
SEE ALSO
exec, fork(), getpid(), getsid(), kill(), setpgid(), setsid()
The Base Definitions volume of POSIX.1‐2008, <unistd.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2013 Edition,
Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, Copyright (C) 2013 by the Institute of Electrical and Electronics Engineers, Inc
and The Open Group. (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) 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 original Standard can be obtained online at
http://www.unix.org/online.html .
Any typographical or formatting errors that appear in this page are most likely to have been introduced
during the conversion of the source files to man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group 2013 SETPGRP(3POSIX)