Documentation made easier
parcat − cat files or fifos in parallel
parcat [−−rm] [−#] file(s) [−#] file(s)
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).
|
−# |
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 send stderr1 and stderr2 to stderr (standard error = file descriptor 2).
|
−−rm |
Remove files after opening. As soon as the files are opened, unlink the files. |
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 in parallel:
mkfifo
freenetproject.org.fifo tange.dk.fifo
traceroute freenetproject.org > freenetproject.org.fifo
&
traceroute tange.dk > tange.dk.fifo &
parcat −−rm *fifo
GNU parcat is part of GNU parallel. Report bugs to <bug−parallel@gnu.org>.
Copyright (C) 2016−2024 Ole Tange, http://ole.tange.dk and Free Software Foundation, Inc.
This 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 the License, or at your option any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY ; without even 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, see <http://www.gnu.org/licenses/>.
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.3−or−later.txt.
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GNU parcat uses Perl.
cat(1), parallel(1)