What's wrong with the perl builtin functions localtime or gmtime? To get a human readable string from epoch time you can simply:

my $str = scalar localtime $s->mtime();
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Substitute localtime with gmtime if you need GMT time. If you want more control over the format of the time, look at POSIX::strftime(), as in the following example:

use POSIX qw/strftime/;
my $str = POSIX::strftime "%F %T", localtime $s->mtime();
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