Re: Query whether a thread is running

[klaus triendl <klaus triendl eu>]

andras toth schrieb:
> Hi Klaus,
>
> Thanks for clarifying it. I need to know whether the thread is already
> running, because I use threads to fetch content from a server when the
> user clicks on a button. And if the button is clicked again whilst the
> previously started thread is not finished yet, I want to return
> without doing anything. On the other hand, if no fetching thread is
> actually running, I start a new one. And I would prefer not to put a
> join on the actually running thread, before starting a new one,
> because then the user interface would hang in case of a second
> request.


Well,

I personally would just start and use one single thread throughout the 
whole application's lifetime in this case.
Also I would rather use messages between threads, this makes your life 
with threads much easier.


With this in mind, I can think of three possibilities how to handle your 
situation:

1) disable the button as long as a server request is pending
2) send multiple asynchronous messages to the worker thread that 
executes these messages one by one and sends back the answer
3) maintain a flag telling you in your main application whether your 
worker thread has already finished the server request


Klaus