GETSID(P) POSIX Programmer's Manual GETSID(P)
getsid - get the process group ID of a session leader
pid_t getsid(pid_t pid);
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.
Upon successful completion, getsid() shall return the process group ID of the session leader of the specified process. Otherwise, it shall
return (pid_t)-1 and set errno to indicate the error.
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.
exec() , fork() , getpid() , getpgid() , setpgid() , setsid() , the Base Definitions 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 Technol-
ogy -- 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 original Standard can be obtained
online at http://www.opengroup.org/unix/online.html .
IEEE/The Open Group 2003 GETSID(P)