Hi Monks!

I use often the localtime() / strftime() couple, but while looking at my collection of one-liners tools, I am puzzled by an epoch translator that displays local time without specifying a format.

If I eval the following code,

perl -le'print localtime 1503403724'

the result is not surprisingly 

4481422711722331

but the following command line filter

echo 1503403724 | perl -pe's/([\d.]+)/localtime $1/e;'

[download]

displays the formated 

Tue Aug 22 14:08:44 2017

Is there some untold magic with the inline loop parameter, or with the executable regex?

For the record, the onle-liner is originaly used to translate some log files with a time-stamp on each line in the form of an epoch date instead of a readable date format. Example:

cat var/nagios.log | perl -pe's/([\d.]+)/localtime $1/e;' | less

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The best programs are the ones written when the programmer is supposed to be working on something else. - Melinda Varian

In reply to one liner automagic strftime() by seki

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