in reply to Optimal Date conversion? (Too much information)

Using Date::Manip:

use strict; use Date::Manip; my $from = 'Wed Dec 29 08:17:04'; my $to = UnixDate($from, "%y-%m-%d_%H:%M:%S"); print "$to\n";

That may not be the fastest method, since Date::Manip is pure Perl and is a bit slow. But it's pretty clear and allows both the input and output format to change as needed.