Re: How can I make a regex apply to each line of a file?

and it might be a good idea to check the return value of your open call open (FILE, "<$footer") or die "Couldn't open file $footer: $!";

Apart from that, it might not be necessary to read the whole file into memory. So you could do something like

open (FILE, "<$footer") or die "Couldn't open file $footer: $!";

while (my $line = <FILE>) {
  $line =~ s/something/something_else/g;
  
  # print changed line
  print $line;

  # do some very complicated other stuff here
}
close FILE;
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But this depends strongly on what you are doing with the lines of the file.

Update: Added comment pointing to more complex operations in while loop.

Thanks davorg, I was aware of your command line solution. Nevertheless I posted in order to stress the fact that there is the while-loop alternative to the memory intensive 'map on array' which was suggested by jj808 and ChemBoy. And I assumed that Kage wanted to do a little bit more than just printing the changed line - although my short snippet didn't show that :)

-- Hofmator

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Re: Re: How can I make a regex apply to each line of a file? by davorg (Chancellor) on Oct 30, 2001 at 21:20 UTC
That's the kind of thing that Perl command line options make very easy: `perl -i.bak -pe 's/something/something else/g' input.txt` [download] -- <http://www.dave.org.uk> "The first rule of Perl club is you don't talk about Perl club."	[reply] [d/l]