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copied!<p>Rather than creating a loop that occasionally calls <code>Application.ProcessMessages</code> you can create a descendant of <code>TThread</code> and move the socket request to the <code>TThread.Execute</code> method. Use TThread.OnTerminate to notify your form(or any other class) when the thread has completed its work.</p> <p>There is <a href="http://radstudiodemos.svn.sourceforge.net/viewvc/radstudiodemos/branches/RadStudio_XE/Delphi/RTL/Threads/" rel="nofollow noreferrer">sample code</a> which gives more details about how to use <code>TThread</code>.</p> <p>There are several other <a href="https://stackoverflow.com/q/3419945/71200">3rd party</a> threading libraries that either provide more flexibility or are easier to use than <code>TThread</code> and I would highly recommend any of them over <code>TThread</code> if you are new to multi-threading.</p> <p>Note: There are some serious <a href="http://delphi.about.com/od/objectpascalide/a/delphi-processmessages-dark-side.htm" rel="nofollow noreferrer">side-effects</a> to using <code>Application.ProcessMessages</code>. You are seeing one of them in your code with the dll unlocking the application's mainform. It breaks the single-threaded UI model the VCL is build upon. <code>ProcessMessages</code> has its place but using threads is more appropriate for the situation you're describing.</p> <pre><code>var Slowpoke: TMyLongRunningProcessThread; procedure MyWaitProc(Completed:TNotifyEvent) begin Slowpoke := TMyLongRunningProcessThread.Create(True); Slowpoke.FreeOnTerminate := True; Slowpoke.OnTerminate := Completed; Slowpoke.Resume; end; </code></pre> <p><code>MyWaitProc</code> returns immediately after starting the thread so the GUI is free to respond to user actions. When the thread terminates it calls the event handler pointed to by <code>Completed</code>.</p> <p>Obviously if you need to retrieve data from the thread you'll want to either have the thread write to an accessible memory location before it Frees itself or remove the <code>FreeOnTerminate</code> so the data can be retreived from the thread through a property.</p>

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