I think this is a typo:

"web service without need of a web service"

And what they mean is that they have to make a script send a response to a browser, without having a traditional webserver (apache and so on) installed.

thank you for correcting the typo, yes I'm looking for some answers related to 'Web Service' without a need of installing ' a Traditional Web Server'

I just wish I did! Now that you've updated your question to be more specific, I can once again recommend Dancer, Catalyst, Mojolicious(::Lite), or even HTTP::Server::Simple.

Here is an example of your desire(borrowed code from the latter):

 #!/usr/bin/perl
 {
 package MyWebServer;
 
 use HTTP::Server::Simple::CGI;
 use base qw(HTTP::Server::Simple::CGI);
 
 my %dispatch = (
     '/bla' => \&resp_bla,
 );
 
 sub handle_request {
     my $self = shift;
     my $cgi  = shift;
   
     my $path = $cgi->path_info();
     my $handler = $dispatch{$path};
 
     if (ref($handler) eq "CODE") {
         print "HTTP/1.0 200 OK\r\n";
         $handler->($cgi);
         
     } else {
         print "HTTP/1.0 404 Not found\r\n";
         print $cgi->header,
               $cgi->start_html('Not found'),
               $cgi->h1('Not found'),
               $cgi->end_html;
     }
 }
 
 sub resp_bla {
     my $cgi  = shift;   # CGI.pm object
     return if !ref $cgi;
     
     print $cgi->header("text/plain"),
           (rand(10) < 5) # pick a random number and see if it is less
+ than 5...
              ? 1 : 0; #...and print 1 if it is, or 0 if it isn't.

 }
 
 } 
 
 # start the server on port 8080
 # access me at   http://localhost:8080/bla
 my $pid = MyWebServer->new(8080)->background();
 print "Use 'kill $pid' to stop server.\n";
[download]

Of course, you will want to do a more interesting check than a random number -- say, whether a file exists, a row is present in a table, or if it is a certain time of day.

~Thomas~ 

"Excuse me for butting in, but I'm interrupt-driven..."