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Xyhm · May 6th, 2008, 4:16 PM

I've developed a program that communicates with another program through anonymous pipes set up by the other program (not written by me).

The problem is that my program keeps crashing as soon as I add something more than just receiving the info. For example, if I add a simple "showMessage", it crashes, but works again if I remove it.

Here is the code:

(Toggle Plain Text)

procedure TArena.read_winboard; 
var text:string[50];
    ch:char;
begin
   while true do
   begin
      text:='';
      repeat
         read(input,ch);
         text:=text+ch;
      until ch=#10;

      //showMessage('this instruction makes the program crash');

      form1.memo1.Lines.Add(text);
 
   end;
end;

Obviously the showMessage-instruction is just an example. If I try to do any parsing of the incoming text (for example sending it to a parser-function of some sort), it crashes. But the code above, devoid of anything extra, doesn't crash, and I can tell by the ouput in the memo that everything is received as expected (and sending info the other way works as well; code not included). So the communication is working.

I hear that buffering can cause problem (even crashing?). Is the input used by that read function using a buffer? And is it that function a real systems call or a part of Delphi (internally doing the systems call)?

I'm really confused right now, and frustrated. I want to start implementing the protocol, but that's hard when not being able to parse the incoming text. Boo hoo.

May 6th, 2008, 4:16 PM	#1
Xyhm Programmer Join Date: Mar 2006 Posts: 60 Rep Power: 3	my program keeps crashing I've developed a program that communicates with another program through anonymous pipes set up by the other program (not written by me). The problem is that my program keeps crashing as soon as I add something more than just receiving the info. For example, if I add a simple "showMessage", it crashes, but works again if I remove it. Here is the code: (Toggle Plain Text) procedure TArena.read_winboard; var text:string[50]; ch:char; begin while true do begin text:=''; repeat read(input,ch); text:=text+ch; until ch=#10; //showMessage('this instruction makes the program crash'); form1.memo1.Lines.Add(text); end; end; procedure TArena.read_winboard; var text:string[50]; ch:char; begin while true do begin text:=''; repeat read(input,ch); text:=text+ch; until ch=#10; //showMessage('this instruction makes the program crash'); form1.memo1.Lines.Add(text); end; end; Obviously the showMessage-instruction is just an example. If I try to do any parsing of the incoming text (for example sending it to a parser-function of some sort), it crashes. But the code above, devoid of anything extra, doesn't crash, and I can tell by the ouput in the memo that everything is received as expected (and sending info the other way works as well; code not included). So the communication is working. I hear that buffering can cause problem (even crashing?). Is the input used by that read function using a buffer? And is it that function a real systems call or a part of Delphi (internally doing the systems call)? I'm really confused right now, and frustrated. I want to start implementing the protocol, but that's hard when not being able to parse the incoming text. Boo hoo.