Dear all, Not being an expert in new-fangled technology ("what do you mean, I'm not allowed to use assembly code?") I am trying to write a .cgi module to handle a form's data. (Primarily using a perl reference book, but that is by the by). My understanding is that I can write a cgi module to create AND handle data from a form. So I did, but I am having trouble making the (software) decision as to how to progress upon code execution. Please note that it is for historical reasons that I use HTML::Tiny and not CGI but that is not part of the problem, unless corrected here 


# Start the page and form creation process as required
$co = HTML::Tiny->new( mode => 'html' );


if ($co->param())
{

    #data returned from the form submission
    print "data present - to be analysed\n";
    $buffer = "";
    if($ENV{'REQUEST_METHOD'} eq "POST")
    {
        # POST method retrieves data by the READ command
        print "POST read\n";
        read(STDIN, $buffer, $ENV{'CONTENT_LENGTH'});
    }
    else
    {
        # GET method retrieves by accessing the relevant environment v
+ariable
        print "Query String\n";
        $buffer = $ENV{'QUERY_STRING'};
    }

    print ("buffer=<p>$buffer</p>");


    if (length ($buffer) > 0)
    {
       # Analyse the form data ....
    }
    else
    {
        print "<p>buffer size is zero<p>";
        exit;
    }
}
else
{
    # No data passed to here by a submit - create the display form tha
+t is required to do so
    print "no data present -to display form\n";
    displayForm();

}

[download]

When I run this code (on a server) I get the diagnostics saying that there is "data present - to be analysed" (as if this call is to handle the form data) but then in the next breath the diagnostics say that the "buffer size is zero". I had a minor thought that the data was somehow being 'retained' somewhere and each time that I ran the script, the 'retained' data was being retested. SO I shut everything down overnight, re-running in the morning, but the same 'problem' presents itself

Q: What is the failing in my software logic here? Have I misread/misunderstood/misinterpreted what I have read in my perl book? As always any help from the monastery would be gratefully received.

Regards ADB

In reply to CGI simple but frustrating fault by gsd4me

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