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I want to get the first 20 or so characters from a number of files.

I've seen examples using cut but they all seem to get the first 20 characters of each line in the file, while I only want the first characters in the file itself (ie. from the first line), nothing more.

Is there a simple way to do this?

interstar
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    The `-c` switch in `head` assumes 1 byte = 1 character. – Thomas N Feb 20 '17 at 18:20
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    Note that the `-c` option is a non-portable extension. – kdhp Feb 20 '17 at 18:22
  • head -c worked on cygwin & centos. head -c brilliant when you need glimpse the contents of say an xml file with no linefeeds – zzapper Apr 16 '18 at 11:10
  • I do not think this should be marked a duplicate, as the OP did not ask that `cat` (or even `cut`) be the tool used. OP simply noted that they had seen examples using `cut`. – bballdave025 Jan 09 '20 at 16:11

2 Answers2

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Complete command would be:

head -c 20 yourFile.txt
dmigo
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Philip Kirkbride
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  • This specifies `20` bytes. Not `20` characters. If you have to handle multibyte characters, use `gawk '{ print substr($1, 1, 20); }' < yourFile.txt` or `python3 -c 'print(input()[:20])' < yourFile.txt` for example. – ynn Mar 24 '23 at 05:10
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Didn't realize the -c option for head was non portable. You can use dd to output the first 20 bytes like so:

dd if=/path/to/infile of=/path/to/outfile  bs=20 count=1

You can omit the of=/path/to/outfile part if you want your result to stdout.

John Mehorter
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