First of all, this is my first post but I have been reading around here first trying to find a solution. Secondly, I haven't a clue about json. I'm an embedded C programmer with limited perl experience. Basically I want to send a simple string of json containing two parameters using a post command to a website and get an integer response. I used the following code that I found on this site as the server saved as a cgi file in the cgi-bin directory of the web server. The webserver is Apache. Do I need to install anything on the webserver to handle json or is it handled by default? 

#!/usr/bin/env perl

use strict;
use warnings;

use CGI ();
use JSON ();

my $q     = CGI->new;
my $json  = JSON->new->utf8;
my $input = $json->decode( $q->param('POSTDATA') );

my $a = $input->{a};
my $b = $input->{b};
my $c = $a + $b;

print $q->header("application/json");
print $json->encode({ c => $c });

[download]

The following, I used as client... 

#!/usr/bin/env perl

use strict;
use warnings;

use JSON ();
use LWP::UserAgent ();
use HTTP::Request::Common qw( POST );

my $data = { a => 40, b => 2 };

my $json = JSON->new->utf8;
my $ua   = LWP::UserAgent->new;

my $req = POST(
    "http://myurl/public_html/cgi-bin/json-addition.cgi",
    Content_Type => 'application/json',
    Content      => $json->encode($data),
);

my $result = $json->decode( $ua->request($req)->decoded_content );
print $result->{c}, "\n";

[download]

I get the following response malformed JSON string, neither array, object, number, string or atom, at character offset 0 (before "Can't connect to myurl...") at json-client.pl line 21. As you can see fellow monks, I am an ignorant soul and need your salvation. Please enlighten me with some of your wisdom?

In reply to json return value by stenasc

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