parcat(1)

1PARCAT(1)                          parallel                          PARCAT(1)
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NAME

6       parcat - cat files or fifos in parallel
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SYNOPSIS

9       parcat [--rm] [-#] file(s) [-#] file(s)
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DESCRIPTION

12       GNU parcat reads files or fifos in parallel. It writes full lines so
13       there will be no problem with mixed-half-lines which you risk if you
14       use:
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16          (cat file1 & cat file2 &) | ...
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18       It is faster than doing:
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20          parallel -j0 --lb cat ::: file*
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22       Arguments can be given on the command line or passed in on stdin
23       (standard input).
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OPTIONS

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

39   Simple line buffered output
40       traceroute will often print half a line. If run in parallel, two
41       instances may half-lines of their output. This can be avoided by saving
42       the output to a fifo and then using parcat to read the two fifos in
43       parallel:
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45         mkfifo freenetproject.org.fifo tange.dk.fifo
46         traceroute freenetproject.org > freenetproject.org.fifo &
47         traceroute tange.dk > tange.dk.fifo &
48         parcat --rm *fifo
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REPORTING BUGS

51       GNU parcat is part of GNU parallel. Report bugs to
52       <bug-parallel@gnu.org>.
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AUTHOR

55       Copyright (C) 2016-2022 Ole Tange, http://ole.tange.dk and Free
56       Software Foundation, Inc.
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LICENSE

59       This program is free software; you can redistribute it and/or modify it
60       under the terms of the GNU General Public License as published by the
61       Free Software Foundation; either version 3 of the License, or at your
62       option any later version.
63
64       This program is distributed in the hope that it will be useful, but
65       WITHOUT ANY WARRANTY; without even the implied warranty of
66       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
67       General Public License for more details.
68
69       You should have received a copy of the GNU General Public License along
70       with this program.  If not, see <http://www.gnu.org/licenses/>.
71
72   Documentation license I
73       Permission is granted to copy, distribute and/or modify this
74       documentation under the terms of the GNU Free Documentation License,
75       Version 1.3 or any later version published by the Free Software
76       Foundation; with no Invariant Sections, with no Front-Cover Texts, and
77       with no Back-Cover Texts.  A copy of the license is included in the
78       file LICENSES/GFDL-1.3-or-later.txt.
79
80   Documentation license II
81       You are free:
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85       to Remix to adapt the work
86
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103
104       Public Domain
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DEPENDENCIES

129       GNU parcat uses Perl.
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