Dependent Origination

perl one-liner

Posted on: November 29, 2011

cat input_file.txt | perl -ne ‘($h, $a, $v) = split(/\|/, $_); print $h, “\n” if $a = 52’

note the | has to be escaped otherwise it will just split between characters

2 Responses to "perl one-liner"

这是干什么的呀?找哪行有 52?

oops
so the input file is line-by-line, each line is separated by | into a couple fields (let’s say three fields) — so this line can give you all the lines of the input file whose one field (this case second field) has a particular value

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