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 &) | ...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 stderr2will send stdout1 and stdout2 to stdout (standard output = file descriptor 1), and send stderr1 and stderr2 to stderr (standard error = file descriptor 2).
Remove files after opening. As soon as the files are opened, unlink the files.
GNU parallel saves output to tempfiles. If the amount of data is bigger than the free disk space, then you can use this technique to do line buffering without saving to disk:
mkfifo slot-{1..5}
seq 10000000 | parallel -j5 --round --pipe 'cat > slot-{%}' &
parcat slot-{1..5} | wcGNU parcat is part of GNU parallel. Report bugs to <bug-parallel@gnu.org>.
Copyright (C) 2016-2020 Ole Tange, http://ole.tange.dk and Free Software Foundation, Inc.
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GNU parcat uses Perl.
cat(1), parallel(1)