i created a datetime constant for use in a few of my scripts that run on Win32 && *NIX, for use in creating temporary directories and files. here's a snippet you may find helpful.

use POSIX;
use constant DATETIME => strftime("%Y-%m-%d_%H-%M-%S", localtime);
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this returns something like "2001-06-25_15-07-32"
your mileage may vary

~Particle