setsid
—
create session and set process group ID
Standard C Library (libc, -lc)
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.
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.
The setsid
() system call will fail if:
- [
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.
The setsid
() system call is expected to be compliant
with the IEEE Std 1003.1-1990
(“POSIX.1”) specification.