From: Dominik Vogt <email@example.com>
To: Zsh Users <firstname.lastname@example.org>
Subject: Using file lines as "input files"
Date: Fri, 8 Jul 2022 21:58:26 +0100 [thread overview]
Message-ID: <Ysiacl2I2eYF+uY4@gmx.de> (raw)
Okay, there's this script that calculates a checksum on each line
of a file by reading each line and passing it to
cat "$INFILE" | while read LINE; do
echo "$LINE" | cksum
This takes about four minutes on a file with 265,000 lines because
of the program call overhead.
Disclaimer: I _know_ this can be done in seconds with perl /
python, but I like to not rely on scripting languages when the
shell can do the job.
So, would it be possible to pass each line in "$INFILE" as a file
argument to "cksum", i.e.
$ chksum Fline1 Fline2 Fline3 ... Fline265000
(Of course without actually splitting the input file - the point
is to get rid of the four minute wait, not generating more
And there's this open file escriptor limit of 1024 too. :-)
Dominik ^_^ ^_^
next reply other threads:[~2022-07-08 20:59 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-07-08 20:58 Dominik Vogt [this message]
2022-07-08 21:58 ` Mikael Magnusson
2022-07-08 22:04 ` Bart Schaefer
2022-07-08 23:17 ` Dominik Vogt
2022-07-09 2:21 ` Mikael Magnusson
2022-07-10 0:42 ` Dominik Vogt
2022-07-10 0:45 ` Dominik Vogt
2022-07-10 3:27 ` Bart Schaefer
2022-07-10 17:49 ` Bart Schaefer
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