First of all, you should use strict; and use warnings;.

On your first attempt, you do something like this:

$timestamp = POSIX::strftime("%m/%d/%Y %I:%M %p", localtime(( stat $fi
+les)[9])); # or change localtime to gmtime
$size = (stat $files)[7];
[download]

You run stat twice, forcing the operating system to grab the same data twice. Why?

Something like this should do the trick in less time:

# Get both pieces of information we need
my ($size, $timestamp) =  ((stat $files)[7, 9]);
# Convert timestamp
$timestamp = POSIX::strftime("%m/%d/%Y %I:%M %p", localtime($timestamp
+);
[download]