#!/usr/bin/perl -w

use strict;

$\ = "\n";

# assume we're running in CGI mode if ...
# ... the SERVER_PORT environment variable is set and 80
# (80 is the usual HTTP post)
print "Content-Type: text/plain; charset=ISO-8859-1\n"
    if defined $ENV{SERVER_PORT} and "80" eq $ENV{SERVER_PORT};

my $file = "/users/faculty/jamie/public_html/course/CS/4173/";
my $mtime = (stat($file))[9];
print "\$file is `$file'";
print "\$file is the location of the course homepage on the server";
print "The course homepage was last modifed at ",
      scalar localtime $mtime, "\n\n";

print "stat \$file will return a list of information about the file \$file";
print "  (stat \$file)[9] is the tenth element of the list";
print "  (stat \$file)[9] is the mtime (modification time) of the file";
print "  the mtime is the number of seconds since the Unix epoch (in 1970)";
print "  (stat $file)[9] is ", (stat $file)[9], "\n";

print "localtime((stat \$file)[9]) will return a list of time data";
print "  for example (localtime((stat \$file)[9]))[2] is the hour";
my $hour = (localtime((stat $file)[9]))[2];
print "              (localtime((stat $file)[9]))[2] is $hour ";
print "              hour $hour is better known as ", hname($hour), "\n";

print "scalar localtime(...) will return the date as a string ",
      "instead of as a list";
print "  scalar (localtime((stat \$file)[9])) is ",
      scalar localtime((stat $file)[9]);

# - - - main ends / subroutine begins - - - #

sub hname {
    my $hour = $_[0];

    return "midnight"   if  0 == $hour;
    return "noon"       if 12 == $hour;
    return "$hour a.m." if $hour < 12;
    $hour -= 12;
    return "$hour p.m.";
} # hname()

## EOF ##