🚀 go-pugleaf

"Lapo Guidi" <lapoguidi@inwind.it> wrote in message
news:457dfd00$1@newsgroups.borland.com...

> There's a way to do that without a TTimer (at client side) with a
> ReadLn inside? Should I use a Thread?

Yes.  Indy is not an asynchronous library, so asynchronous operations have
to be performed synchronously inside their own threads.


Gambit

Yes, I supposed that.

At client side I do that:
when user update a cell at Row, Col I send a command to the server
TCPClient->SendCmd("UPDATE "+IntToStr(Row)+" "+IntToStr(Col));
So the Server receive the command and Client get Reply and Response back.
But how could I code a Thread at client side to receive the data from the 
Server when the Client didn't send a command?
Could you help me giving me a little snip of code?
Thanks

Lapo 

Well, I coded a TThread descendant that perform a ReadLn without timeout (I 
found a previous posted answer you gave to somebody hehe).
But I have again a question:
when the Client send a command with SendCmd, function doesn't return untill 
Reply and Response;
the receiving thread I coded will steal the Reply and the Response that 
SendCmd is waiting for?
I'm a bit confused and I'm sorry if these are dumb questions.
Thanks.

Lapo 

"Lapo Guidi" <lapoguidi@inwind.it> wrote in message
news:457f31bf@newsgroups.borland.com...

> At client side I do that:
> when user update a cell at Row, Col I send a command to the server
> TCPClient->SendCmd("UPDATE "+IntToStr(Row)+" "+IntToStr(Col));

That will not work anymore if you use a reading thread, as SendCmd()
performs its own reading internally.  So you have the possibility of the
thread receiving data that SendCmd() is expecting, and vice versa.

> So the Server receive the command and Client get Reply and Response
> back. But how could I code a Thread at client side to receive the data
> from the Server when the Client didn't send a command?

Simply call one of the appropriate reading methods of the connection in a
loop for the lifetime of the thread.  Look at the source code of the
TIdTelnet component for an example.


Gambit

"Lapo Guidi" <lapoguidi@inwind.it> wrote in message
news:457f3780$1@newsgroups.borland.com...

> when the Client send a command with SendCmd, function doesn't return
> untill Reply and Response; the receiving thread I coded will steal the
Reply
> and the Response that SendCmd is waiting for?

Yes, it can (and vice versa, SendCmd() can steal data that the thread may be
waiting on).  Which is why you can't use SendCmd() anymore if you are using
a reading thread.  You will have to use WriteLn() instead, and then do all
of your reply processing inside of the thread as well.  So you are going to
have to design your data protocol in such as way that the thread will be
able to tell which packets are command replies and which ones are not.

One way around that is to wrap the connection in a critical section.  Then
you can "lock" the connection before calling SendCmd() and "unlock" it
afterwards.  Then the thread will not be able to read from the socket while
it is busy waiting for a command reply.

Othrwise, you will just have to go back to using a Timer again and forget
the thread altogether.


Gambit

Thanks very much Remy,
You helped me a lot as usual.

Lapo