in reply to Debugging Perl .cgi forms

It's a little tough to tell what's happening from what you have given us. But here are a few things to check:

- are you using CGI.pm?
- have you printed a proper HTTP header at the top of your output?
- have you successfully produced a "Hello World" page to test your basic approach?
- have you included something like the following near the top of your script to help you trace your errors?

use CGI qw(:standard);
use CGI::Carp;
use CGI::Carp qw(fatalsToBrowser);
local $SIG{__WARN__} = \&Carp::cluck;

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If none of this gets you closer to a solution, slim down your script to the minimum that still produces the error and post both the script and the output you get when you run from the command line.

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Re: Re: Debugging Perl .cgi forms
by nysus (Parson) on Apr 01, 2001 at 06:38 UTC
    I know the first 3 are all covered. I can get the script working, but I often make errors while modifying the script (I'm new at this) and that's when I get the ISE's.

    In regards to your last suggestion:
    --I have "use CGI;" at the top of my script
    --I have tried using CGI::Carp qw(fatalsToBrowser) but it didn't provide any useful information. I have never tried the other two lines (and don't know what they are) but I will slap them in there and see what happens.

    Thanks.

[reply]
      nysus, is sounds like you are over the big hurdles. This is the point where I just proceed incrementally, adding more material a bit at a time until something goes wrong.

      If you get to a point where no amount of staring at the screen brings enlightenment, show us some code and output. We love looking at the real stuff.

      But be sure you 'use strict;' and have '-w' in your hashbang line or you will get gently (?) scolded.  ;-)

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[d/l]
[select]
        Here it is by popular demand. I've only put in the code that I changed which broke the script. Look at the password setting to see my level of frustration. :) 
        #!/usr/bin/perl -w

use strict;
use CGI;
my $query = new CGI;
my $error_message = "";
my $pwd = "";

###############################################
#                          #
# Variable initiation                  #
#                          #
###############################################

my $form_submission_check = "Submit";                    # Set to the 
+name of an object on the form

###############################################
#                          #
# Script program logic                  #
#                          #
###############################################

if ($query->param('cancel')) {   
    &get_password;
} elsif ($query->param('change1')) {
           &change_password();
} elsif ($query->param('change2')) {
    &process_change_password();
} else {
        $pwd = $query->param('password');
        if ($pwd eq "suckmydick") {
        $pwd = 1;
                &form;
        } else {
        &get_password();
    }
}

        [download]
        Thanks.
[reply]
[d/l]
      I slapped those lines in there but get no extra info in my browser.
[reply]

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