in reply to Appending time to each line

Use your datetime function in place of localtime:

$text = "the\nquick\nbrown\nfox\n";;
$text = join "\n", map{ localtime()." $_" } split "\n", $text;;

print $text;;
Tue May 21 10:42:09 2013 the
Tue May 21 10:42:09 2013 quick
Tue May 21 10:42:09 2013 brown
Tue May 21 10:42:09 2013 fox

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