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Hi, there:

Following is my code, basically I try to simply XOR a 20MB file line by line
with a key
then save it in a file. I am using the lastest ActivePerl in Win2000.

The error I got is,
The instruction at "0x2808698b" referenced memory at "0x00000004".
The memory couldn't be "written".

Click OK to terminate...
Click CANCEL to debug...

What happened?

Thanks.




#!/usr/bin/perl
use POSIX;

open(FIL, "./line_merged.all");
@page_in = <FIL>;
close(FIL);

$key = "This is my key";
$j = 0;
open(FIL, ">./encrypted.all");
binmode FIL;
foreach $line (@page_in) {
if( $j % 100 == 0 ) {
print "\n\n\nLine $j started here: \n";
print "\n" . $line;
}
$j = $j + 1;
$mult = ceil( length( $line ) / length( $key ) ) + 1;
for( $i = 0; $i < $mult; $i = $i + 1) {
$key = $key . $key;
}
$key = substr($key, 0, length($line));
$line = $key ^ $line ;
# print "\n" . $key;
# print "\n\nAfter Encryption\n" . $line;
print FIL $line;

# $line = $key ^ $line ;
# print "\n\nAfter Decryption\n" . $line;
}
close(FIL);

Hi Kelvin

I've used Active Perl some years on my job. Your code looks quite ordinary
to me. I nearly always use strict and use warnings though.

use POSIX I've never used. What does it do ?

regards Ejner


On Tue, 14 Sep 2004 10:24:56 +0800, Kelvin wrote:

> Hi, there:
>
> Following is my code, basically I try to simply XOR a 20MB file line by line
> with a key
> then save it in a file. I am using the lastest ActivePerl in Win2000.
>
> The error I got is,
> The instruction at "0x2808698b" referenced memory at "0x00000004".
> The memory couldn't be "written".
>
> Click OK to terminate...
> Click CANCEL to debug...
>
> What happened?
>
> Thanks.
>
>
>
>
> #!/usr/bin/perl
> use POSIX;
>
> open(FIL, "./line_merged.all");
> @page_in = <FIL>;
> close(FIL);
>
> $key = "This is my key";
> $j = 0;
> open(FIL, ">./encrypted.all");
> binmode FIL;
> foreach $line (@page_in) {
> if( $j % 100 == 0 ) {
> print "\n\n\nLine $j started here: \n";
> print "\n" . $line;
> }
> $j = $j + 1;
> $mult = ceil( length( $line ) / length( $key ) ) + 1;
> for( $i = 0; $i < $mult; $i = $i + 1) {
> $key = $key . $key;
> }
> $key = substr($key, 0, length($line));
> $line = $key ^ $line ;
> # print "\n" . $key;
> # print "\n\nAfter Encryption\n" . $line;
> print FIL $line;
>
> # $line = $key ^ $line ;
> # print "\n\nAfter Decryption\n" . $line;
> }
> close(FIL);

Ejner Borgbjerg wrote:

> I've used Active Perl some years on my job. Your code looks quite ordinary
> to me. I nearly always use strict and use warnings though.
>
> use POSIX I've never used. What does it do ?

perldoc POSIX

-Joe