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PARALLEL(1)			   moreutils			   PARALLEL(1)

NAME
       parallel	- run programs in parallel

SYNOPSIS
       parallel	[options] [command]-- [argument	...]

       parallel	[options]-- [command ...]

DESCRIPTION
       parallel	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.

       If no command is	specified before the --, the commands after it are
       instead run in parallel.

OPTIONS
       -j maxjobs
	   Use to limit	the number of jobs that	are run	at the same time.

       -l maxload
	   Wait	as needed to avoid starting new	jobs when the system's load
	   average is not below	the specified limit.

       -i
	   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.

       -n
	   Number of arguments to pass to a command at a time. Default is 1.
	   Incompatible	with -i

EXAMPLE
       parallel	sh -c "echo hi;	sleep 2; echo bye" -- 1	2 3

       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.

       parallel	-j 3 ufraw -o processed	-- *.NEF

       This runs three ufraw processes at the same time	until all of the NEF
       files have been processed.

       parallel	-j 3 --	ls df "echo hi"

       This runs three independent commands in parallel.

EXIT STATUS
       Its exit	status is the combination of the exit statuses of each command
       ran, ORed together. (Thus, if any one command exits nonzero, parallel
       as a whole will exit nonzero.)

NOTES
       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.

AUTHOR
       Tollef Fog Heen

moreutils			  2009-07-02			   PARALLEL(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLE | EXIT STATUS | NOTES | AUTHOR

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