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Re: doing a search and replace on a large file

by b10m (Vicar)
on Apr 14, 2004 at 12:48 UTC ( #345029=note: print w/replies, xml ) Need Help??

in reply to Re: doing a search and replace on a large file
in thread doing a search and replace on a large file

Minor tweak: since the OP wants to "delete" lines that do not match a certain pattern, I'd change the unless into an if. That way, you "save" the lines that do match the pattern ;-)

open IN, "<$bigfile" or die "Can't open $bigfile: $!\n"; open OUT, ">$newfile" or die "Can't open $newfile: $!\n"; while(<IN>) { print OUT $_ if /the pattern in question/; } close OUT; close IN;

All code is usually tested, but rarely trusted.

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LanX my favourite don't tell me the proof of concept is good enough for production anecdote
[ambrus]: ah, it's one of thos
[Eily]: what, there's a difference between proof of concept and production?
[LanX]: 20 years ago traders were complaining about the latency of the trading system...
[ambrus]: I'm currently in the process of rewriting my proof of concept programs. They sort of developped organically as I was experimenting, so now I've got an ugly mess of multiple programs and one-liners held together by nothing. I'll have to rewrite them to som
[ambrus]: ething that's both cleanly organized and mostly automated.
LanX in train, bad connection
[Corion]: ambrus: Yeah - we're in that situation too, except that there is no time to do the reorganizing :-/
[LanX]: ... so my boss started a project with the newest sun servers and invited the traders to come on weekend to test it... and they were so pleased, that they forced him to keep it in production...
[ambrus]: Corion: sure, this is the long-term plan. The short term is that I have to run this ungodly mess to get results from the new input data today.

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