Since you said "post", you will need LWP::UserAgent

use strict;
use LWP::UserAgent;

my $url = "http://your url"; 
my $ua = LWP::UserAgent->new; 
my $res = $ua->post($url); 
if($res->is_success()){
   my $content = $res->content();
   if($content =~ /true/){
      print "looks good\n";
   }elsif($content =~ /false/){
      print "something is wrong\n";
   }else{
      print "how can that be?\n";
   }
}else{
    print "Uh-oh, time to work!\n";
}
[download]

(Not tested)