You have the following:

=item B<-a, --amount>

Search for files older than <amount> days, mandatory.
[download]

In two days, there are 2 * 24 * 60 * 60 or 172800 seconds, thus it seemed that the following was needed:

$amount = $amount * 24 * 60 * 60;
[download]

since one day equals 24 * 60 * 60 or 86400 seconds. Additionally, the following worked when I ran it using the above formula for $amount:

$result =
  grep { /.+\.$suffix$/ and $time - ( $_->stat )[9] >= $amount }
  io($dir)->all;
[download]

An equivalent search can be done using File::Find::Rule:

$result = File::Find::Rule->file()
                          ->maxdepth(1)
                          ->name(qr/.+\.$suffix$/i)
                          ->mtime(">= $amount")
                          ->in($dir);
[download]

And the following, too, but grepping on days old instead of using mtime:

$result = grep { -M >= $amount / 86400 } # Convert back to days
          File::Find::Rule->file()
                          ->maxdepth(1)
                          ->name(qr/.+\.$suffix$/i)
                          ->in($dir);
[download]

All three methods produced the same result, even when an equivalent constant was used for the days in the last grep.

After adjusting the $amount formula, your original code produced the same result, too:

    $result =
      grep { $_ == 1 }
      map  { $time - $_ >= $amount }
      map  { ( $_->stat )[9] }  # e.g i'm interested in this...
      grep { $_->name =~ /.+\.$suffix$/ } # ...and this
      io($dir)->all;
[download]

Thus, all four code snippets produced identical results.

Sorry about that awkward typo: should have been hours...

«The Crux of the Biscuit is the Apostrophe»

Ah, yes--that makes sense! Used the hours calculation for all four snippets:

$amount = $amount * 60 * 60;
[download]

and got identical results, until 79 hours was used (a result difference of 2), but I suspect the division in the grep { -M >= $amount / 86400 } yields a different precision.

Interestingly, IO::All didn't see the file "song自然之歌," but File::Find::Rule did (and should have).

"An equivalent search can be done using File::Find::Rule"

This is simply true, but what i wanted to do was this:

• Not using File::Find
• Not using File::Find::Rule"
• Not using qx(find...[options])
• Bothering myself with map/grep

Thank you very much for your advice and the insights you gave to me. Regards, Karl

«The Crux of the Biscuit is the Apostrophe»

I really should have said that I wasn't suggesting a different or better way by using File::Find::Rule. Only used it to verify your results (like inter-rater reliability). Yours was a good map/grep piece.

Nice update, by the way...