Re: bash, expressions, ???
"Egor Tur" <worldeb@ukr.net> writes:
> Hi.
> Who can explain?
> ps ax | grep lpd
> 398 ? S 0:00 lpd Waiting
> 5593 pts/13 S 0:00 grep lpd
> ps ax | grep [l]pd
> 398 ? S 0:00 lpd Waiting
>
> What do [l]?
As far as grep is concerned, [l] is a regular expression that matches
any single character that is a lowercase l. lp[rd] would match either
lpr or lpd. The important effect here is that lpd and [l]pd both
match 'lpd', but neither matches '[l]pd', so the grep process itself
isn't included in the ps listing.
--
David Maze dmaze@debian.org http://people.debian.org/~dmaze/
"Theoretical politics is interesting. Politicking should be illegal."
-- Abra Mitchell
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