🚀 go-pugleaf

AlexB wrote:

>It's part of JVCL's JvgMailSlot (slightly modified):

First, I have to wonder why you are asking Java/VCL/Delphi questions in a C++ group...

>procedure TJvgMailSlotServer.OnTimer(Sender: TObject);

Why is this on a timer?
There are much better ways such as threads and Read Events.

>var
>  MsgSize: DWORD;
>  MsgNumber: DWORD;
>  Read: DWORD;
>  Buffer: Pointer;
>begin
>  // Determining if there's message
>  if not GetMailSlotInfo(FHandle, nil, MsgSize, @MsgNumber, nil)

I don't know Delphi, but that looks quite wrong.
I would expect
	GetMailSlotInfo(FHandle, nil, @MsgSize, @MsgNumber, nil)

>      FData.Size:=MsgSize; // Allocate memory
>      Buffer:=FData.Memory;
>      // Reading message
>      if ReadFile(FHandle, Buffer^, MsgSize, Read, nil)

Similarly
      if ReadFile(FHandle, Buffer^, MsgSize, @Read, nil)

>    Result:=WriteFile(FHandle, MessageData, MessageLength, Written,nil);
    Result:=WriteFile(FHandle, MessageData, MessageLength, @Written,nil);

>Send works normally (always returns true).
>Local messaging ('.\') with length up to 64K work without problems.
>Network messaging (i.e. where name of computer was specified):
> - up to 425 bytes in any case
> - up to 1365 bytes after installation of NetBEUI.

In other words, One Packet.
You need to prefix your message with a message size,
and have the server keep reading until it gets all of the message.
Then have the sender break up the message into packet size.

>Server never see network messages longer then 1365 bytes
>(i.e. MsgSize=MAILSLOT_NO_MESSAGE).
>
>MSDN says that for long messages (up to 64K) mailslots require "SMB
>session". I have no idea how to check the presence of SMB session.

<quote>
The data in a mailslot message can be in any form, but cannot
be larger than 424 bytes when sent between computers. To send
messages that are larger than 424 bytes between computers,
use named pipes or Windows Sockets instead.</quote>
http://msdn2.microsoft.com/en-us/library/aa365130.aspx