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2.\"	$NetBSD: setpgid.2,v 1.8 1995/02/27 12:36:55 cgd Exp $
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31.\"     @(#)setpgid.2	8.1 (Berkeley) 6/4/93
32.\"
33.Dd June 4, 1993
34.Dt SETPGID 2
35.Os
36.Sh NAME
37.Nm setpgid ,
38.Nm setpgrp
39.Nd set process group
40.Sh SYNOPSIS
41.Fd #include <unistd.h>
42.Ft int
43.Fn setpgid "pid_t pid" "pid_t pgrp"
44.Ft int
45.Fn setpgrp "pid_t pid" "pid_t pgrp"
46.Sh DESCRIPTION
47.Fn setpgid
48sets the process group of the specified process
49.Ar pid
50to the specified
51.Ar pgrp .
52If
53.Ar pid
54is zero, then the call applies to the current process.
55.Pp
56If the invoker is not the superuser, then the affected process
57must have the same effective user ID as the invoker or be a descendant
58of the invoking process.
59.Sh RETURN VALUES
60.Fn setpgid
61returns 0 when the operation was successful.
62If the request failed, \-1 is returned and the global variable
63.Va errno
64indicates the reason.
65.Sh ERRORS
66.Fn setpgid
67will fail and the process group will not be altered if:
68.Bl -tag -width Er
69.It Bq Er EACCES
70The value of the
71.Fa pid
72argument matches the process ID of a child process of the calling process,
73and the child process has successfully executed one of the exec functions.
74.It Bq Er EINVAL
75The value of the
76.Fa pgrp
77argument is less than zero.
78.It Bq Er EPERM
79The effective user ID of the requested process is different
80from that of the caller and the process is not a descendant
81of the calling process.
82.It Bq Er ESRCH
83The value of the
84.Fa pid
85argument does not match the process ID of the calling process or of a
86child process of the calling process.
87.El
88.Sh SEE ALSO
89.Xr getpgrp 2
90.Sh STANDARDS
91.Fn setpgrp
92is identical to
93.Fn setpgid ,
94and is retained for calling convention compatibility with historical
95versions of
96.Bx .
97.Pp
98The
99.Fn setpgid
100function conforms to
101.St -p1003.1-88 .
102