If you can, use Text::Diff. 
use Text::Diff;
my $foo = Text::Diff::diff $file1, $file2, \%options;

[download]
%options include STYLE (unified, context or classic etc), OUTPUT and a couple others.

/prakash

In reply to Re: diff output; unix commands by PrakashK
in thread diff output; unix commands by poprishchin

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