setsid (8) ( Linux man: Команды системного администрирования )
BSD mandoc
NAME
setsid
- create session and set process group ID
LIBRARY
Lb libc
SYNOPSIS
#include <unistd.h> pid_t
setsid (void);
DESCRIPTION
The
setsid ();
system call creates a new session.
The calling process is the session leader of the new session, is the
process group leader of a new process group and has no controlling
terminal.
The calling process is the only process in either the session or the
process group.
RETURN VALUES
Upon successful completion, the
setsid ();
system call returns the value of the process group ID of the new process
group, which is the same as the process ID of the calling process.
If an error occurs,
setsid ();
returns -1 and the global variable
errno
is set to indicate the error.
ERRORS
The
setsid ();
system call will fail if:
Bq Er EPERM
The calling process is already a process group leader, or the process
group ID of a process other than the calling process matches the process
ID of the calling process.