mirror of
https://git.FreeBSD.org/ports.git
synced 2024-12-11 02:50:24 +00:00
88 lines
3.4 KiB
Groff
88 lines
3.4 KiB
Groff
'\" t
|
|
.\" Title: parallel
|
|
.\" Author: Joey Hess
|
|
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
|
|
.\" Date: 2009-07-02
|
|
.\" Manual: moreutils
|
|
.\" Source: moreutils
|
|
.\" Language: English
|
|
.\"
|
|
.TH "PARALLEL" "1" "2009\-07\-02" "moreutils" "moreutils"
|
|
.\" -----------------------------------------------------------------
|
|
.\" * Define some portability stuff
|
|
.\" -----------------------------------------------------------------
|
|
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
.\" http://bugs.debian.org/507673
|
|
.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html
|
|
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
.ie \n(.g .ds Aq \(aq
|
|
.el .ds Aq '
|
|
.\" -----------------------------------------------------------------
|
|
.\" * set default formatting
|
|
.\" -----------------------------------------------------------------
|
|
.\" disable hyphenation
|
|
.nh
|
|
.\" disable justification (adjust text to left margin only)
|
|
.ad l
|
|
.\" -----------------------------------------------------------------
|
|
.\" * MAIN CONTENT STARTS HERE *
|
|
.\" -----------------------------------------------------------------
|
|
.SH "NAME"
|
|
parallel \- run programs in parallel
|
|
.SH "SYNOPSIS"
|
|
.HP \w'\fBparallel\fR\fB\-\-\fR\ 'u
|
|
\fBparallel\fR [options] [command]\fB\-\-\fR [argument\ \&.\&.\&.]
|
|
.HP \w'\fBparallel\fR\fB\-\-\fR\ 'u
|
|
\fBparallel\fR [options]\fB\-\-\fR [command\ \&.\&.\&.]
|
|
.SH "DESCRIPTION"
|
|
.PP
|
|
\fBparallel\fR
|
|
runs the specified command, passing it a single one of the specified arguments\&. This is repeated for each argument\&. Jobs may be run in parallel\&. The default is to run one job per CPU\&.
|
|
.PP
|
|
If no command is specified before the \-\-, the commands after it are instead run in parallel\&.
|
|
.SH "OPTIONS"
|
|
.PP
|
|
\fB\-j maxjobs\fR
|
|
.RS 4
|
|
Use to limit the number of jobs that are run at the same time\&.
|
|
.RE
|
|
.PP
|
|
\fB\-l maxload\fR
|
|
.RS 4
|
|
Wait as needed to avoid starting new jobs when the system\*(Aqs load average is not below the specified limit\&.
|
|
.RE
|
|
.PP
|
|
\fB\-i\fR
|
|
.RS 4
|
|
Normally the command is passed the argument at the end of its command line\&. With this option, any instances of "{}" in the command are replaced with the argument\&.
|
|
.RE
|
|
.PP
|
|
\fB\-n\fR
|
|
.RS 4
|
|
Number of arguments to pass to a command at a time\&. Default is 1\&. Incompatible with \-i
|
|
.RE
|
|
.SH "EXAMPLE"
|
|
.PP
|
|
\fBparallel sh \-c "echo hi; sleep 2; echo bye" \-\- 1 2 3\fR
|
|
.PP
|
|
This runs three subshells that each print a message, delay, and print another message\&. If your system has multiple CPUs, parallel will run some of the jobs in parallel, which should be clear from the order the messages are output\&.
|
|
.PP
|
|
\fBparallel \-j 3 ufraw \-o processed \-\- *\&.NEF\fR
|
|
.PP
|
|
This runs three ufraw processes at the same time until all of the NEF files have been processed\&.
|
|
.PP
|
|
\fBparallel \-j 3 \-\- ls df "echo hi"\fR
|
|
.PP
|
|
This runs three independent commands in parallel\&.
|
|
.SH "EXIT STATUS"
|
|
.PP
|
|
Its exit status is the combination of the exit statuses of each command ran, ORed together\&. (Thus, if any one command exits nonzero,
|
|
\fBparallel\fR
|
|
as a whole will exit nonzero\&.)
|
|
.SH "NOTES"
|
|
.PP
|
|
All output to stdout and stderr is serialised through a corresponding internal pipe, in order to prevent annoying concurrent output behaviour\&. Note that serialisation is not done on any other file descriptors and file position based access to a nonstandard file descriptor might have unexpected results\&.
|
|
.SH "AUTHOR"
|
|
.PP
|
|
Tollef Fog Heen
|