News Group Posts

shell script pattern matching

From: johnd@sco.COM (John DuBois)
Newsgroups: comp.unix.sco.misc
Subject: Re: Stupid pattern matching question
Date: 14 Dec 2000 23:08:30 GMT
Message-ID: <91bjte$t4r$1@hobbes.sco.com> 
References: <m146aRO-000CFsC@egps.com> 


In article <m146aRO-000CFsC@egps.com>,
Nachman Yaakov Ziskind  <awacs@egps.com> wrote:
+Your-data-goes-here NNNN::NNNN more-data-very-important
+
+where 'NNNN' is a four digit number (some sort of key, I presume) and
+*should* be equal on both sides of the double colon. If it isn't,
+trouble is afoot. Supposedly the '::' sequence is guaranteed to be unique 
+in each record.
+
+
+So, how do I dump out those records where the # doesn't match?

database-dump | grep -v ' \([0-9][0-9][0-9][0-9]\)::\1 '

If your-data-goes-here has a specific format, you can replace the initial space
with a pattern that ensures that the part you're testing actually appears where
it's supposed to.

See the "back-reference expression" section in the regexp(M) man page for an
explanation of the \(...\) and \num stuff in the pattern above.

        John
-- 
John DuBois     johnd@sco.com       KC6QKZ/AE
I wish to God these calculations had been executed by steam. - Charles Babbage

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