I have this piece of code to capture HTTP request from browser:

sub recv_req {
    my $browser = shift;
    my $content_length = 0;
    my $req = "";
    while (1) {
        my $chunk;
        $browser->recv($chunk, 10000);
        if ($chunk =~ m/Content-Length: (\d*)/) {
            $content_length = $1;
            print "content_length = $content_length\n";
        }
        $req .= $chunk;
        last if ($chunk =~ "\r\n\r\n");
    }
    $req =~ /(.*?)\r\n\r\n(.*)/s;
    if (length($2) > 0) {
        $content_length -= length($2);
        print "after -, content_length = $content_length\n";
        print "[$2]\n";# I added this line minutes ago to capture $2
    }
    while ($content_length > 0) {
        my $chunk;
        $browser->recv($chunk, $content_length);
        $req .= $chunk;
        $content_length -= length($chunk);
    }
    return $req;
}

[download]

For this line, 

print "after -, content_length = $content_length\n";

[download]

I expect it to print 0 for the last time it goes into the loop (if ever). However it prints -2 occasionaly (I cannot remember whether this happens to other web site, but for sure some particular request for this site)

This has been going on for a while, but today I decided to figure out what's going on, so I added:

print "[$2]\n";

[download]

to capture the content.

In one instance, I captured this, when I tried to delete a message:

after -, content_length = -2
[node_id=3628&deletemsg_540904478=yup&op=message&message=&message_send
+=talk&.cgi   #this line break here is caused by screen width
fields=deletemsg_540904478
]

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It seems to me that there is a "\r\n" at the very end of the content, which is not counted in Content-Length, and that's where that -2 comes from.

I think there is a standard comformance issue somewhere, but I would like others to double check my script.

In reply to wrong Content-Length by pg

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