According to tye's wishes, I will just update this node.

After writing a nice little paragraph on the -s file test operator and (stat $file)[7], i then realized that the topic was about date and not size (holy brain fart.)

Anywho. I will have to agree with DamnDirtyApe's post and say that

my $date = (stat $file)[9];
[download]

is the best way. Also, here's a link to more information on the stat function. You can get information like size, modified date, uid, gid, mode, etc. of a file using that function.