Current Perl documentation can be found at perldoc.perl.org.

Here is our local, out-dated (pre-5.6) version:

If you want to retrieve the time at which the file was last read, written, or had its meta-data (owner, etc) changed, you use the -M, -A, or -C filetest operations as documented in the perlfunc manpage. These retrieve the age of the file (measured against the start-time of your program) in days as a floating point number. To retrieve the ``raw'' time in seconds since the epoch, you would call the stat function, then use localtime(), gmtime(), or POSIX::strftime() to convert this into human-readable form.

Here's an example:

    $write_secs = (stat($file))[9];
    printf "file %s updated at %s\n", $file,
        scalar localtime($write_secs);

If you prefer something more legible, use the File::stat module (part of the standard distribution in version 5.004 and later):

    use File::stat;
    use Time::localtime;
    $date_string = ctime(stat($file)->mtime);
    print "file $file updated at $date_string\n";

Error checking is left as an exercise for the reader.