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";
print OUT $_ if /the pattern in question/;
All code is usually tested, but rarely trusted.