This is a simple hello world example plugin skeleton for WHM plugins, intended primarily to give people somewhere to start. 

#!/usr/bin/perl
#WHMADDON:helloworld:Hello World <b>Example</b>

###############################################################################
# This is an example hello world WHM plugin feel free to modify it as you see fit
###############################################################################
# Load general use case perl modules
use lib '/usr/local/cpanel';
use Cpanel::cPanelFunctions ();
use Cpanel::Form            ();
use Cpanel::Config          ();
use Whostmgr::HTMLInterface ();

use Whostmgr::ACLS          ();
###############################################################################
print "Content-type: text/html\r\n\r\n";
# Check user has root permissions
Whostmgr::ACLS::init_acls();
if ( !Whostmgr::ACLS::hasroot() ) {
# User is not root, tell them where to go
print "You need to be root to see the hello world example.\n";

exit();
}

# Parse input parameters from GET and POST into $FORM{} for later use
my %FORM     = Cpanel::Form::parseform();

# Print a WHM Header
Whostmgr::HTMLInterface::defheader( "Hello World Example Plugin",'/path/to/logo.gif', '/cgi/addon_helloworld.cgi' );

# Print General Output
print "<p>Hello world indeed...</p>";

# End Example

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