Perl script to remove lines with a certain pattern in a file or list of files - originally from http://stackoverflow.com/users/47529/chaos

gistfile1.txt

#!/usr/bin/perl

use IO::Handle;

my $pat = shift(@ARGV) or
    die("Usage: $0 pattern files\n");
die("Usage $0 pattern files\n")
    unless @ARGV;

foreach my $file (@ARGV) {
    my $io = new IO::Handle;
    open($io, $file) or
        die("Cannot read $file: $!\n");
    my @file = <$io>;
    close($io);
    foreach my $line (@file) {
        if($line =~ /$pat/o) {
            $line = '';
            $found = 1;
            last;
        }
    }
    if($found) {
        open($io, ">$file") or
            die("Cannot write $file: $!\n");
        print $io @file;
        close($io);
    }
}

I use it combined with a find operation so that all my uses of the @Version with the Svn: $id keyword are deleted (they aren't really needed after a git migration)

find . -type f -name "*.class.php" -exec ~/line_cleaner.pl " @Version " {} ;