GETSID(3P)

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
getsid — get the process group ID of a session leader

SYNOPSIS

#include <unistd.h>

pid_t getsid(pid_t pid);

DESCRIPTION
The getsid() function shall obtain the process group ID of the process that is the session leader of the process specified by pid. If pid is (pid_t)0, it specifies the calling process.

RETURN VALUE
Upon successful completion, getsid() shall return the process group ID of the session leader of the specified process. Otherwise, it shall return -1 and set errno to indicate the error.

ERRORS
The getsid() function shall fail if:

EPERM
    The process specified by pid is not in the same session as the calling process, and the implementation does not allow access to the process group ID of the session leader of that process from the calling process.

ESRCH
    There is no process with a process ID equal to pid.

The following sections are informative.

EXAMPLES
None.

APPLICATION USAGE
None.

RATIONALE
None.

FUTURE DIRECTIONS
None.

SEE ALSO
exec, fork(), getpid(), getpgid(), setpgid(), setsid()

The Base Definitions volume of POSIX.1-2017, <unistd.h>

COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C) 2018 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 original Standard can be obtained online at http://www.opengroup.org/unix/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 .