xref: /dragonfly/lib/libc/sys/setsid.2 (revision 1de703da)
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32.\"	@(#)setsid.2	8.1 (Berkeley) 6/4/93
33.\" $FreeBSD: src/lib/libc/sys/setsid.2,v 1.10.2.2 2001/12/14 18:34:01 ru Exp $
34.\" $DragonFly: src/lib/libc/sys/setsid.2,v 1.2 2003/06/17 04:26:47 dillon Exp $
35.\"
36.Dd June 4, 1993
37.Dt SETSID 2
38.Os
39.Sh NAME
40.Nm setsid
41.Nd create session and set process group ID
42.Sh LIBRARY
43.Lb libc
44.Sh SYNOPSIS
45.In unistd.h
46.Ft pid_t
47.Fn setsid void
48.Sh DESCRIPTION
49The
50.Fn setsid
51function creates a new session.
52The calling process is the session leader of the new session, is the
53process group leader of a new process group and has no controlling
54terminal.
55The calling process is the only process in either the session or the
56process group.
57.Sh RETURN VALUES
58Upon successful completion, the
59.Fn setsid
60function returns the value of the process group ID of the new process
61group, which is the same as the process ID of the calling process.
62If an error occurs,
63.Fn setsid
64returns -1 and the global variable
65.Va errno
66is set to indicate the error.
67.Sh ERRORS
68The
69.Fn setsid
70function will fail if:
71.Bl -tag -width Er
72.It Bq Er EPERM
73The calling process is already a process group leader, or the process
74group ID of a process other than the calling process matches the process
75ID of the calling process.
76.El
77.Sh SEE ALSO
78.Xr setpgid 2 ,
79.Xr tcgetpgrp 3 ,
80.Xr tcsetpgrp 3
81.Sh STANDARDS
82The
83.Fn setsid
84function is expected to be compliant with the
85.St -p1003.1-90
86specification.
87