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I think you're misunderstanding the packet format. When you say that the representation is in "binary", it doesn't mean the binary representation that you get by doing unpack "B*"; it means that your data is packed as if it's in a binary structure. So you have the right operator (pack), you just have the wrong pack template.

I think that this will work for you:

    my $data = "LOGON USERNAME=NAME PASSWORD=PASS\0";
    my $packet = pack "CnCCNnn",
                2,                 ## sync byte
                length($data)+13,  ## message size
                13,                ## header size
                hex("4c"),         ## message type
                1,                 ## sequence ID
                0,                 ## protocol ID
                1;                 ## version number
    $packet .= $data;
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That pack template ("CnCCNnn") says to pack the list of values (the rest of the arguments to pack) in the following way:

unsigned char value (1 byte)
short in network order (2 bytes)
unsigned char value (1 byte)
unsigned char value (1 byte)
long in network order (4 bytes)
short in network order (2 bytes)
short in network order (2 bytes)

This varies from your use of pack in two important ways. First, we no longer use 'unpack "B*"', because the point of that is to take a binary structure and make it into a human-readable string that looks like a sequence of bits. That's not what you want: you want to send the data to the server as a binary structure.

Second, you can't just use 'pack "N"'; that packs everything as a network-order long, which is 4 bytes. You don't want everything to be 4 bytes; some things are 1 byte, some are 2, some are 4. You have to vary you pack template depending on that.

In reply to Re: Socket Newbie (perl newbie, too...) by btrott
in thread Socket Newbie (perl newbie, too...) by Sabacthani

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