LabWindows tcp client lost connection with a visual studio server when the window make other operations

[dorianp69]

I have an application LabWindows/cvi with a main window with menus and buttons.

This main window has a software module that is a client of a TCP/IP connection where the server is in another application created in Microsoft Visual Studio 2019. The name of the server is "SC".

When I select a menu of the main LabWindows/cvi window and I left the menu open without selecting an item menu, the client TCP/IP stop receiving message from the server, while the server send correctly the messages.

I attach the software module that is a client of a TCP/IP connection writed in C in LabWindows/cvi

The LabWindows/cvi application with the main window and the server TCP/IP application are executed in the same PC.

[GabelDaniel]

hello

in the ClientSCTCPRead() func you have a while loop that attempts to read continuously from TCP.

Try To add somewhere ProcessSystemEvents() in the loop  

[RobertoBozzolo · Accepted solution]

Unfortunately in your scenario ProcessSystemEvents will not solve your problems. As you can read here,

when ProcessSystemEvents handles an event that starts a tracking loop, such as the user pulling down a menu, ProcessSystemEvents does not return until the tracking loop completes. In the case of pulling down a menu, the tracking loop does not complete until the user dismisses the menu.

The usual way to address this kind of issues is to move to a multithreaded framework that guarantees that spawned threads can continue working independent from UI happenings. UI timers are affected by this issue as well so they are not the soution: only asynchronous timers and threads are guaranteed to work.

[dorianp69 · Accepted solution]

Thank you Roberto for the reply,

I solved the problem creating a separate thread that manage the tcp client connection. I use the tcp/MultiThreadingClient.prj sample.

Thank you and Best Regards