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author | rgrimes <rgrimes@FreeBSD.org> | 1994-05-27 05:00:24 +0000 |
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committer | rgrimes <rgrimes@FreeBSD.org> | 1994-05-27 05:00:24 +0000 |
commit | be22b15ae2ff8d7fe06b6e14fddf0c5b444a95da (patch) | |
tree | a18a706dffa5baf86a3b12bbfb4f81caa097f349 /lib/libc/sys/getpgrp.2 | |
parent | 2a27bd86e6002c871e3b5561a5334653bb222a77 (diff) | |
download | FreeBSD-src-be22b15ae2ff8d7fe06b6e14fddf0c5b444a95da.zip FreeBSD-src-be22b15ae2ff8d7fe06b6e14fddf0c5b444a95da.tar.gz |
BSD 4.4 Lite Lib Sources
Diffstat (limited to 'lib/libc/sys/getpgrp.2')
-rw-r--r-- | lib/libc/sys/getpgrp.2 | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/lib/libc/sys/getpgrp.2 b/lib/libc/sys/getpgrp.2 new file mode 100644 index 0000000..88812b7 --- /dev/null +++ b/lib/libc/sys/getpgrp.2 @@ -0,0 +1,101 @@ +.\" Copyright (c) 1983, 1991, 1993 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" This product includes software developed by the University of +.\" California, Berkeley and its contributors. +.\" 4. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" @(#)getpgrp.2 8.1 (Berkeley) 6/4/93 +.\" +.Dd June 4, 1993 +.Dt GETPGRP 2 +.Os BSD 4.2 +.Sh NAME +.Nm getpgrp +.Nd get process group +.Sh SYNOPSIS +.Fd #include <unistd.h> +.Ft pid_t +.Fn getpgrp "void" +.Sh DESCRIPTION +The process group of the current process is returned by +.Fn getpgrp . +.Pp +Process groups are used for distribution of signals, and +by terminals to arbitrate requests for their input: processes +that have the same process group as the terminal are foreground +and may read, while others will block with a signal if they attempt +to read. +.Pp +This call is thus used by programs such as +.Xr csh 1 +to create +process groups +in implementing job control. +The +.Fn tcgetpgrp +and +.Fn tcsetpgrp +calls +are used to get/set the process group of the control terminal. +.Sh SEE ALSO +.Xr setpgid 2 , +.Xr termios 4 +.Sh HISTORY +The +.Nm +function call appeared in +.Bx 4.0 . +.Sh STANDARDS +The +.Fn getpgrp +function conforms to IEEE Std 1003.1-1988 +.Pq Dq Tn POSIX . +.Sh COMPATABILITY +This version of +.Fn getpgrp +differs from past Berkeley versions by not taking a +.Fa "pid_t pid" +argument. +This incompatibility is required by +.St -p1003.1-88 . +.Pp +From the +.St -p1003.1-88 +Rationale: +.sp +4.3BSD provides a +.Fn getpgrp +function that returns the process group ID for a specified process. +Although this function is used to support job control, all known +job-control shells always specify the calling process with this +function. +Thus, the simpler System V +.Fn getpgrp +suffices, and the added complexity of the 4.3BSD +.Fn getpgrp +has been omitted from POSIX.1. |