External Plugin returning too quickly

Bert Freudenberg bert at impara.de
Mon Nov 21 09:21:28 UTC 2005

Am 21.11.2005 um 02:28 schrieb Brad Fuller:

> Bert Freudenberg wrote:
>> Did you wrap the usleep() into a while loop checking for EINTR?
> googling, I found many instances of usleep to be a problem in  
> multithreading. One place said usleep sets an alarm signal to wait.  
> When it occurs, usleep returns. SIGALRM should not be blocked and  
> if it is, usleep will exit. This was my problem.
> I abandoned usleep and instead tried nanosleep. The result was the  
> same - I heard just a blip.
> So, I wrapped the call to nanosleep with blocking the signals with  
> pthread_sigmask(), called nanosleep and then unblocked the signals.
> This worked.
> But, I don't know why. I still don't understand how this would  
> effect the call to the library from Squeak and not as a standalone.  
> What is different, or added, with Squeak that is not with the  
> standalone test?

Squeak uses SIGALARM itself, unless you run the VM with -notimer.  
Which you should not do unless you do not care about performance.

- Bert -

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