use strict;
use warnings;

while (<DATA>) {
    s/a/x/g unless $. & 1;
    print;
}

__DATA__
Anyone know a way to apply a
substitution in a file to every
other line rather
than the hole file?

[download]

Prints:

Anyone know a way to apply a
substitution in x file to every
other line rather
thxn the hole file?

[download]
DWIM is Perl's answer to Gödel

In reply to Re: Search and replace in all odd lines by GrandFather
in thread Search and replace in all odd lines by greatshots

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