Tips on Unix utilities and related topics from @JohnDCook.
Joined August 2011
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'The enjoyment of one's tools is an essential ingredient of successful work.' -- Donald E. Knuth
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Awk to Perl translator: metacpan.org/pod/App::a2p
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Count the number of commas in the first row of a file:
awk -F, "NR == 1 {print NF}" foo.csv
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Print the numbers of the lines that don't have 42 commas and print how many commas they do have.
awk -F, "NF != 42 {print NR, NF}" foo.csv
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The sed command p prints. For example, print lines 3 through 7 of a file: sed -n '3,7p' somefile
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Unix tool tip retweeted
Print lines in foo.txt containing non-ASCII characters, along with line numbers.
perl -wnlE 'say qq{$. $_} if /[^\x00-\x7f]/' foo.txt
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Logged into a computer today and was surprised it runs Unix, not Linux. And my first thought was a movie line:
invidio.us/watch?v=dFUlAQ…
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Sort a file in case-insensitive order: sort -f. 'f' for 'fold,' i.e. fold upper and lower case together
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“GUI-minded programs seldom lend themselves to being used as components in larger tools.” — Tom Christiansen
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