*sigh* The following code seems to work fine on my PC but I get an error message (one I haven't managed to come up with before) when I run it from my web site. 
#!/usr/bin/perl -w

use CGI::Carp qw(fatalsToBrowser);
use CGI;
 my $req = new CGI;
 my $sort = $req->param("sort");
 if(!$sort){  $sort = "id";}

print "Content-type: text/html\n\n";
print "Click on a header to sort.<br>";
print "<table><tr><td><a href=\"?sort=id\">ID</a></td>\n<td><a href=\"
+?sort=info\">Info</a></td>\n<td><a href=\"?sort=graphics\">Graphics</
+a></td>\n<td><a href=\"?sort=friendly\">Friendly</a></td>\n<td><a hre
+f=\"?sort=techno\">Techno</a></td>\n<td><a href=\"?sort=entertain\">E
+ntertain</a></td>\n<td><a href=\"?sort=average\">Average</a></td>\n<t
+d><a href=\"?sort=hits\">Hits</a></td>\n</tr>";

opendir(DIR, "members");
my @files = grep( /\.dat/, readdir(DIR) );
@files = sort(@files);
closedir(DIR);

$num = 0;
foreach $file(@files){
         open (TXTFILE, "members/$file") or die "Can't open $file";
         @lines = <TXTFILE>;
         close(TXTFILE);
         tr/\r\n//d for @lines;
         $hit = $lines[0];
         if($hit >0){
                  $info = sprintf("%.2f", ($lines[1]/$hit) );
                  $graphics = sprintf("%.2f", ($lines[2]/$hit) );
                  $friendly = sprintf("%.2f", ($lines[3]/$hit) );
                  $techno = sprintf("%.2f", ($lines[4]/$hit) );
                  $entertain = sprintf("%.2f", ($lines[5]/$hit) );
                  $rate = sprintf("%.2f", (($info + $graphics + $frien
+dly + $techno + $entertain)/5) );
                  $id = $file;
                  $id =~ s/\.dat//;

                  $all_hashes[$num] = ({
                                   ID => $id,
                                   info => $info,
                                   graphics => $graphics,
                                   friendly => $friendly,
                                   techno => $techno,
                                   entertain => $entertain,
                                   rate => $rate,
                                   hit => $hit,
                                   });

                  }#end if hit
$num++;
}#end for each file

if($sort eq "id" ){ @all_hashes = sort { $a->{ID} <=> $b->{ID} } @all_
+hashes;}
if($sort eq "info" ){ @all_hashes = sort { $a->{info} <=> $b->{info} }
+ @all_hashes;}
if($sort eq "graphics" ){ @all_hashes = sort { $a->{graphics} <=> $b->
+{graphics} } @all_hashes;}
if($sort eq "friendly" ){ @all_hashes = sort { $a->{friendly} <=> $b->
+{friendly} } @all_hashes;}
if($sort eq "techno" ){ @all_hashes = sort { $a->{techno} <=> $b->{tec
+hno} } @all_hashes;}
if($sort eq "entertain" ){ @all_hashes = sort { $a->{entertain} <=> $b
+->{entertain} } @all_hashes;}
if($sort eq "average" ){ @all_hashes = sort { $a->{rate} <=> $b->{rate
+} } @all_hashes;}
if($sort eq "hits" ){ @all_hashes = sort { $a->{hit} <=> $b->{hit} } @
+all_hashes;}

for(@all_hashes){
     print "<tr><td>$_->{ID}</td>\n<td>$_->{info}</td>\n<td>$_->{graph
+ics}</td>\n<td>$_->{friendly}</td>\n<td>$_->{techno}</td>\n<td>$_->{e
+ntertain}</td>\n<td>$_->{rate}</td>\n<td>$_->{hit}</td>\n</tr>";
}
print "</table>";

[download]
The error message is: 
Click on a header to sort.
ID Info Graphics Friendly Techno Entertain Average Hits 
Content-type: text/html 
Software error:
Modification of a read-only value attempted at line 50. 
For help, please send mail to the webmaster (support@aplus.net), givin
+g this error message and the time and date of the error.

[download]
Line 50 is if($sort eq "id" ){ @all_hashes = sort { $a->{ID} <=> $b->{ID} } @all_hashes;} What have I done (now)?

In reply to Error in code - read-only value? by katgirl

Title:
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