#!/usr/bin/perl
# Author: Peter R. Wood, http://prwdot.org/

use strict;

####
#### Configuration
####

# Path to 'screencapture' utility
my $screencapture = "/usr/sbin/screencapture";

# Path to ImageMagick 'convert' utility
my $convert = "/usr/local/bin/convert";

# Path to 'who' command
my $who = "/usr/bin/who";

# Directory to which the screencapture should be saved
my $destination = "/Path/To/Your/Web/Dir";

# Desired filename. Do not include the three-letter extension.
my $filename = "screencapture";

# Desired Format. Choose one of 'png' 'jpg' 'pdf'
my $file_format = "png";

######### MAIN PROGRAM

## Check to see if someone is logged in to the console. If not, skip it.
my $wholist = `$who`;
chomp($wholist);
if ( $wholist =~ /console/go ) {

    # Run screencapture
    my $screencap_command = "$screencapture $destination/$filename.pdf";
    system($screencap_command) || die "Couldn't run $screencap_command: $!\n";
    print "Capture was successful.\n";

    # Do we need to convert the file?
    if ( $file_format ne 'pdf' ) {
        my $convert_command =
"$convert $destination/$filename.pdf $file_format:$destination/$filename.$file_format";
        system($convert_command) || die "Couldn't run $convert_command: $!\n";
        print "Convert was successful.\n";
    }
}
else {
    die "Nobody logged in - nothing to capture.\n";
}