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<p class="MsoNormal">Hi Eliot, all,</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I'm baffled by this example:</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">p := [Semaphore new wait] fork.</p>
<p class="MsoNormal">Processor yield.</p>
<p class="MsoNormal">p resume explore</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I expected to get an error but the process just gets out of the semaphore and finishes happily.</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">#resume comment says:</p>
<p class="MsoNormal"> Primitive. Allow the process that the receiver represents to continue. Put
</p>
<p class="MsoNormal"> the receiver in line to become the activeProcess. *Fail if the receiver is
</p>
<p class="MsoNormal"> already waiting in a queue (in a Semaphore or ProcessScheduler)*. Fail if</p>
<p class="MsoNormal"> the receiver's suspendedContext is not a context.</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The following works as expected - p sits at the semaphore:</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">p := [Semaphore new wait] fork.</p>
<p class="MsoNormal">Processor yield.</p>
<p class="MsoNormal">p explore</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This works as well (with the new VM) - p backs up and sits before the wait:</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">p := [Semaphore new wait] fork.</p>
<p class="MsoNormal">Processor yield.</p>
<p class="MsoNormal">p suspend.</p>
<p class="MsoNormal">p explore</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">And this works too indeed - p sits at the semaphore again after suspend.</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">p := [Semaphore new wait] fork.</p>
<p class="MsoNormal">Processor yield.</p>
<p class="MsoNormal">p suspend.</p>
<p class="MsoNormal">p resume explore</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Is this a bug? Or is the comment just outdated? </p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I've been trying to figure out possible ways how to prevent resuming a process being terminated (other than setting its suspendedContext to nil) and this unexpected behavior gave me a real hard time :)</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Many thanks for your help.</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Best regards,</p>
<p class="MsoNormal">Jaromir</p>
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