Re: NSTimer

[Richard Frith-Macdonald]

On 27 Feb 2009, at 11:15, David Chisnall wrote:
> > The behavior on MacOS when I tested it was strange and  
> > inconsistent ... sometime the loop returned immediately as  
> > documented, sometimes it blocked.  My suspicion is that MacOS-X has  
> > an undocumented feature of sometimes putting input sources in the  
> > run loop
>
> This is not undocumented.  The NSRunloop documentation clearly states:
>
> > Manually removing all known input sources and timers from the run  
> > loop is not a guarantee that the run loop will exit. Mac OS X can  
> > install and remove additional input sources as needed to process  
> > requests targeted at the receiver’s thread.

I meant undocumented in the sense that it does not specify the  
conditions under which it can occur.

For instance, I had a test program which did *nothing* other than  
create an autorelease pool and run the runloop in the main thread ...  
but it still blocked.  Doing the same thing in a second thread, the  
loop terminated immediately.
Perhaps the main runloop will always block in practice under OSX, but  
I would not rely on it.