if you want to know everything about the time, use the localtime function:

my $mtime = (stat $filename)[9];

my($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst) = localtime($m
+time);
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All list elements are numeric, and come straight out of a struct tm. ... In particular this means that #mon has the range 0..11, $wday has the range 0..6, and the year has had 1,900 subtracted from it. (You can remember which ones are 0-based because those are the ones you're always using as subscripts into 0-based arrays containing the month and day names.)