xref: /freebsd/lib/libsys/getsid.2 (revision 8269e7673cf033aba67dab8264fe719920c70f87)
1*8269e767SBrooks Davis.\" Copyright (c) 1997 Peter Wemm <peter@FreeBSD.org>
2*8269e767SBrooks Davis.\"
3*8269e767SBrooks Davis.\" Redistribution and use in source and binary forms, with or without
4*8269e767SBrooks Davis.\" modification, are permitted provided that the following conditions
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14*8269e767SBrooks Davis.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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24*8269e767SBrooks Davis.Dd August 19, 1997
25*8269e767SBrooks Davis.Dt GETSID 2
26*8269e767SBrooks Davis.Os
27*8269e767SBrooks Davis.Sh NAME
28*8269e767SBrooks Davis.Nm getsid
29*8269e767SBrooks Davis.Nd get process session
30*8269e767SBrooks Davis.Sh LIBRARY
31*8269e767SBrooks Davis.Lb libc
32*8269e767SBrooks Davis.Sh SYNOPSIS
33*8269e767SBrooks Davis.In unistd.h
34*8269e767SBrooks Davis.Ft pid_t
35*8269e767SBrooks Davis.Fn getsid "pid_t pid"
36*8269e767SBrooks Davis.Sh DESCRIPTION
37*8269e767SBrooks DavisThe session ID of the process identified by
38*8269e767SBrooks Davis.Fa pid
39*8269e767SBrooks Davisis returned by
40*8269e767SBrooks Davis.Fn getsid .
41*8269e767SBrooks DavisIf
42*8269e767SBrooks Davis.Fa pid
43*8269e767SBrooks Davisis zero,
44*8269e767SBrooks Davis.Fn getsid
45*8269e767SBrooks Davisreturns the session ID of the current process.
46*8269e767SBrooks Davis.Sh RETURN VALUES
47*8269e767SBrooks DavisUpon successful completion, the
48*8269e767SBrooks Davis.Fn getsid
49*8269e767SBrooks Davissystem call
50*8269e767SBrooks Davisreturns the session ID of
51*8269e767SBrooks Davisthe specified process; otherwise, it returns a value of -1 and
52*8269e767SBrooks Davissets errno to indicate an error.
53*8269e767SBrooks Davis.Sh ERRORS
54*8269e767SBrooks DavisThe
55*8269e767SBrooks Davis.Fn getsid
56*8269e767SBrooks Davissystem call
57*8269e767SBrooks Daviswill succeed unless:
58*8269e767SBrooks Davis.Bl -tag -width Er
59*8269e767SBrooks Davis.It Bq Er ESRCH
60*8269e767SBrooks Davisif there is no process with a process ID equal to
61*8269e767SBrooks Davis.Fa pid .
62*8269e767SBrooks Davis.El
63*8269e767SBrooks Davis.Pp
64*8269e767SBrooks DavisNote that an implementation may restrict this system call to
65*8269e767SBrooks Davisprocesses within the same session ID as the calling process.
66*8269e767SBrooks Davis.Sh SEE ALSO
67*8269e767SBrooks Davis.Xr getpgid 2 ,
68*8269e767SBrooks Davis.Xr getpgrp 2 ,
69*8269e767SBrooks Davis.Xr setpgid 2 ,
70*8269e767SBrooks Davis.Xr setsid 2 ,
71*8269e767SBrooks Davis.Xr termios 4
72*8269e767SBrooks Davis.Sh HISTORY
73*8269e767SBrooks DavisThe
74*8269e767SBrooks Davis.Fn getsid
75*8269e767SBrooks Davissystem call appeared in
76*8269e767SBrooks Davis.Fx 3.0 .
77*8269e767SBrooks DavisThe
78*8269e767SBrooks Davis.Fn getsid
79*8269e767SBrooks Davissystem call is derived from its usage in
80*8269e767SBrooks Davis.At V .
81