in reply to Perl, Apache, Dr. Watson, and my scripts

the error message refers to $param being undefined...

it looks like the parameter name is not defined and (in my version of CGI.pm at least) this looks like a problem... 

# from CGI.pm

sub parse_params {
    my($self,$tosplit) = @_;
    my(@pairs) = split(/[&;]/,$tosplit);
    my($param,$value);
    foreach (@pairs) {
    ($param,$value) = split('=',$_,2);
    $value = '' unless defined $value;
    $param = unescape($param);

# this is where the situation goes unchecked...
# CGI::Util::unescape returns undef if $param is undef
# none the wiser and no error checking!

    $value = unescape($value);
    $self->add_parameter($param);
    push (@{$self->{$param}},$value);
    }
}

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so my guess is that you have a URL like: 
http://your.site.here/cgi-bin/script.pl?param1=value1&=value2&param3=v
+alue3

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which is lacking "param2" and would cause the issue you are seeing. try adding... 
next unless defined $param;

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where I put the 3 line comment inside the parse_params sub

hope this helps

update: if this does turn out to be the problem you may want to check if the most recent version has the same problem - if so you can email the author(s) and let him/her/them know you have discovered a bug 

   larryk                                          
perl -le "s,,reverse killer,e,y,rifle,lycra,,print"

Replies are listed 'Best First'.
print "true" unless $MrCromeDome ne "dumbass"
by MrCromeDome (Deacon) on Aug 16, 2001 at 20:17 UTC
    Yeah, that will always print true ;)

    It's pretty much the situation that you describe above. . . just a little bit different. Instead of this: 

    http://cygnus/cgi-bin/view.cgi?document=12345678&=name

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    I have this: 
    http://cygnus/cgi-bin/view.cgi?document=12345678&&tab=name

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    Note the &&. If I make it a single &, it seems to work fine. Seems like I made a pretty fatal typo there. I don't know if that indicates a problem with CGI or not (my guess is not), but I do know that things work fine without the second &.

    Thanks for your help :)
    MrCromeDome

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[d/l]
[select]
      typo - yes
      fatal - shouldn't have been (IMHO)

      CGI.pm is basically doing 
      #!/usr/bin/perl -w
use strict;

$_ = 'test1=1&&test3=3';

for ( split '&' ) {
    my($param,$value) = split '=';
    print "param='$param'\n";
    print "value='$value'\n";
    
    # and using $param even though it is undefined the 2nd time
}

      [download]
      You said that both versions of apache are the same but it looks like the two versions of CGI.pm are different - you can check ~ line 22 of CGI.pm for the version number.

      if they are the same then I'm stumped - otherwise you should probably upgrade to the newer one at least as it looks like it is handling malformed URLs properly (this type anyway). 

         larryk                                          
perl -le "s,,reverse killer,e,y,rifle,lycra,,print"
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[d/l]

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