#!/usr/bin/perl
use strict;
use warnings;
while (<DATA>) {
s/(?:^.*?>>\h*|\G(?!^))\K./\\$&/g;
}
__DATA__
Aenean placerat >> /example/alpha.txt
est et rutrum ultrices >> /example/beta.txt
dolor nibh ultricies nulla >> /example/gamma delta.txt
IyEvdXNyL2Jpbi9wZXJsCgp1c2Ugc3RyaWN0Owp1c2Ugd2FybmluZ3M7Cgp3aGlsZSAoPERBVEE+KSB7CiAgICBzLyg/Ol4uKj8+PlxoKnxcRyg/IV4pKVxLLi9cXCQmL2c7CiAgICBwcmludDsKfQoKX19EQVRBX18KQWVuZWFuIHBsYWNlcmF0ID4+IC9leGFtcGxlL2FscGhhLnR4dAplc3QgZXQgcnV0cnVtIHVsdHJpY2VzID4+IC9leGFtcGxlL2JldGEudHh0CmRvbG9yIG5pYmggdWx0cmljaWVzIG51bGxhID4+IC9leGFtcGxlL2dhbW1hIGRlbHRhLnR4dA==