[c0ncrete]

You can pass any information on to the external script via the use of @ARGV, as shown below.

my $player = "YoMomma";
my $zonesn = "butcher";

# current full working directory
( my $cwd = $0 ) =~ s/(?:(?!\\|\/)\S)+$//;

# you'll want to add some sanity checks to make sure you have valid data here
sub EVENT_ENTERZONE
{

	# hash with zonesn as keys and external scripts to run for the zone
	my %signal_zone = (
		butcher => "signal_butcher.pl",
		cauldron => "signal_cauldron.pl"
	);

	{
		local @ARGV = ($player);
		do "$cwd$signal_zone{$zonesn}";
	}
}

EVENT_ENTERZONE();

Above code calls the following (signal_butcher.pl located in the same folder):

print $ARGV[0];

Printed result:

YoMomma