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28 .\" @(#)getpgrp.2 8.1 (Berkeley) 6/4/93
29 .\" $FreeBSD: src/lib/libc/sys/getpgrp.2,v 1.11.2.6 2001/12/14 18:34:00 ru Exp $
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46 .Fn getpgid "pid_t pid"
48 The process group of the current process is returned by
50 The process group of the process identified by
58 returns the process group of the current process.
60 Process groups are used for distribution of signals, and
61 by terminals to arbitrate requests for their input: processes
62 that have the same process group as the terminal are foreground
63 and may read, while others will block with a signal if they attempt
66 This call is thus used by programs such as
70 in implementing job control.
76 are used to get/set the process group of the control terminal.
81 Upon successful completion, the
83 call returns the process group of the specified process;
84 otherwise, it returns a value of \-1 and sets
86 to indicate the error.
90 differs from past Berkeley versions by not taking a
93 This incompatibility is required by
103 function that returns the process group ID for a specified process.
104 Although this function is used to support job control, all known
105 job-control shells always specify the calling process with this
110 suffices, and the added complexity of the
113 has been omitted from POSIX.1.
114 The old functionality is available from the
122 there is no process whose process ID equals
132 function call is expected to conform to
137 function call appeared in
141 function call is derived from its usage in System V Release 4.