GNU parcat

NAME
parcat - cat files or fifos in parallelSYNOPSIS
parcat [--rm] [-#] file(s) [-#] file(s)DESCRIPTION
GNU parcat reads files or fifos in parallel. It writes full lines so there will be no problem with
mixed-half-lines which you risk if you use:(cat file1 & cat file2 &) | ...
It is faster than doing:
parallel -j0 --lb cat ::: file*Arguments can be given on the command line or passed in on stdin (standard input).

OPTIONS-#Arguments following this will be sent to the file descriptor #. E.g.
parcat -1 stdout1 stdout2 -2 stderr1 stderr2
will send stdout1 and stdout2 to stdout (standard output = file descriptor 1), and sendstderr1 and stderr2 to stderr (standard error = file descriptor 2).
--rm
Remove files after opening. As soon as the files are opened, unlink the files.

EXAMPLES
Simple line buffered output
traceroute will often print half a line. If run in parallel, two instances may half-lines of their output.
This can be avoided by saving the output to a fifo and then using parcat to read the two fifos inparallel:
mkfifo freenetproject.org.fifo tange.dk.fifo
traceroute freenetproject.org > freenetproject.org.fifo &traceroute tange.dk > tange.dk.fifo &parcat --rm *fifo

REPORTING BUGS
GNU parcat is part of GNU parallel. Report bugs to <bug-parallel@gnu.org>.

AUTHOR
Copyright (C) 2016-2024 Ole Tange, http://ole.tange.dk and Free Software Foundation, Inc.

LICENSEThis program is free software; you can redistribute it and/or modify it under the terms of the GNU
General Public License as published by the Free Software Foundation; either version 3 of theLicense, or at your option any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; withouteven the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program. If not,Page 1

GNU parcat
see <http://www.gnu.org/licenses/>.

Documentation license IPermission is granted to copy, distribute and/or modify this documentation under the terms of theGNU Free Documentation License, Version 1.3 or any later version published by the Free Software
Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. Acopy of the license is included in the file LICENSES/GFDL-1.3-or-later.txt.

Documentation license II
You are free:
to Shareto copy, distribute and transmit the work
to Remix
to adapt the work
Under the following conditions:
Attribution
You must attribute the work in the manner specified by the author or licensor (but notin any way that suggests that they endorse you or your use of the work).
Share AlikeIf you alter, transform, or build upon this work, you may distribute the resulting work
only under the same, similar or a compatible license.
With the understanding that:
WaiverAny of the above conditions can be waived if you get permission from the copyrightholder.
Public Domain
Where the work or any of its elements is in the public domain under applicable law,that status is in no way affected by the license.
Other Rights
In no way are any of the following rights affected by the license:
Your fair dealing or fair use rights, or other applicable copyrightexceptions and limitations;
The author's moral rights;
Rights other persons may have either in the work itself or in how thework is used, such as publicity or privacy rights.
NoticeFor any reuse or distribution, you must make clear to others the license terms of thiswork.
A copy of the full license is included in the file as LICENCES/CC-BY-SA-4.0.txt

DEPENDENCIES
GNU parcat uses Perl.

Page 2

GNU parcat

SEE ALSO
cat(1), parallel(1)Page 3