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<p class="MsoNormal">Hi Juan,</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">the update indeed works, thanks! </p>
<p class="MsoNormal">An observation though: if you do:</p>
<p class="MsoNormal">1) Semaphore new wait</p>
<p class="MsoNormal">2) Alt+.</p>
<p class="MsoNormal">3) Proceed</p>
<p class="MsoNormal">It disrupts the screen and 'restore display' from the World menu is needed; nothing serious, just reporting because I don't know whether this is to be expected or not :)</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">There's one issue I'd very much like to discuss:</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">s := Semaphore new.</p>
<p class="MsoNormal">[1/0. s signal] fork.</p>
<p class="MsoNormal">s wait</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">When I first ran this example I kind of hoped the UI would not freeze and would open a debugger on the ZeroDivide. I can't see any reason why not behave like that but both Squeak and Cuis freeze because the UI waits on the semaphore and
the forked process requests the UI to open a debugger but the UI is stuck at the semaphore :)</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">My expectation was the system would spawn a new UI that would open the debugger but I have no experience with UIs and debuggers and can imagine it may be very tricky :)</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I'd be very interested in your opinion how the above example could/should be handled by the UI.</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Of course if you run the example in a non-UI process it works as expected but it'd be nice I guess if running it in the UI would behave similarly :)</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">[s := Semaphore new.</p>
<p class="MsoNormal">[1/0. s signal] fork.</p>
<p class="MsoNormal">s wait] fork</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Many thanks!</p>
<p class="MsoNormal">Jaromir</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNoSpacing"><span lang="CS">--</span></p>
<p class="MsoNoSpacing"><strong><span style="font-family:"Calibri Light",sans-serif;color:#333333;font-weight:normal">Jaromír Matas</span></strong><span style="font-family:"Calibri Light",sans-serif;color:#555555"><o:p></o:p></span></p>
<p class="MsoNoSpacing"><span style="font-family:"Calibri Light",sans-serif;color:#2E75B6">mail@jaromir.net</span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<div style="mso-element:para-border-div;border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in">
<p class="MsoNormal" style="border:none;padding:0in"><b>From: </b><a href="mailto:JuanVuletich@zoho.com">Juan Vuletich</a><br>
<b>Sent: </b>Saturday, July 2, 2022 1:54<br>
<b>To: </b><a href="mailto:cuis-dev@lists.cuis.st">Discussion of Cuis Smalltalk</a><br>
<b>Cc: </b><a href="mailto:JuanVuletich@zoho.com">Juan Vuletich</a>; <a href="mailto:mail@jaromir.net">
Jaromir Matas</a><br>
<b>Subject: </b>Re: [Cuis-dev] Freezing UI - can't interrupt via Alt+.</p>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="color:black">On 7/1/2022 9:45 AM, Juan Vuletich via Cuis-dev wrote:
<o:p></o:p></span></p>
<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
<p class="MsoNormal"><span style="color:black">On 7/1/2022 8:17 AM, Jaromir Matas via Cuis-dev wrote:
<o:p></o:p></span></p>
<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
<p class="MsoNormal"><span style="color:black">Hi Juan, all,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"> <o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">I wonder why this can’t be interrupted by Alt+.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"> <o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">Semaphore new wait<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"> <o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">The system returns a message “Can not interrupt background process” and the image has to be closed.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"> <o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">The same happens in this case:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"> <o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">s := Semaphore new.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">[1/0. s signal] fork.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">s wait<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"> <o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">It not only freezes the UI but is not even recoverable…<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"> <o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">Thanks,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">jaromir<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"> <o:p></o:p></span></p>
<p class="MsoNoSpacing"><span lang="CS" style="color:black">--</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNoSpacing"><strong><span style="font-family:"Calibri Light",sans-serif;font-weight:normal">Jaromír Matas</span></strong><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNoSpacing"><a href="mailto:mail@jaromir.net">mail@jaromir.net</a><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"> <o:p></o:p></span></p>
</blockquote>
<p class="MsoNormal"><span style="color:black"><br>
Hi Jaromir,<br>
<br>
The problem is in #handleUserInterrupt, in particular in #processTakingMostCPU. #handleUserInterrupt runs on a high priority process, so the first thing it needs to figure out is which process to interrupt. I wrote that code believing that alt+. would need
to interrupt busy code, and it works in that case. It doesn't work if the UI process is waiting and never resumed, as it is not "busy".<br>
<br>
We need to do better here. I won't be able to work on this for the next few days, but would be very happy if any of you folks suggest / code a solution.<br>
<br>
Thanks,<br>
<br>
<o:p></o:p></span></p>
<pre>-- </pre>
<pre>Juan Vuletich</pre>
<pre><a href="http://www.cuis-smalltalk.org">www.cuis-smalltalk.org</a></pre>
<pre><a href="https://github.com/Cuis-Smalltalk/Cuis-Smalltalk-Dev">https://github.com/Cuis-Smalltalk/Cuis-Smalltalk-Dev</a></pre>
<pre><a href="https://github.com/jvuletich">https://github.com/jvuletich</a></pre>
<pre><a href="https://www.linkedin.com/in/juan-vuletich-75611b3">https://www.linkedin.com/in/juan-vuletich-75611b3</a></pre>
<pre><a href="https://independent.academia.edu/JuanVuletich">https://independent.academia.edu/JuanVuletich</a></pre>
<pre><a href="https://www.researchgate.net/profile/Juan-Vuletich">https://www.researchgate.net/profile/Juan-Vuletich</a></pre>
<pre><a href="https://patents.justia.com/inventor/juan-manuel-vuletich">https://patents.justia.com/inventor/juan-manuel-vuletich</a></pre>
<pre><a href="https://twitter.com/JuanVuletich">https://twitter.com/JuanVuletich</a></pre>
</blockquote>
<p class="MsoNormal"><span style="color:black"><br>
Just pushed a fix. Please review it. It is update #5346.<br>
<br>
Thanks!<br>
<br>
<o:p></o:p></span></p>
<pre>-- </pre>
<pre>Juan Vuletich</pre>
<pre><a href="http://www.cuis-smalltalk.org">www.cuis-smalltalk.org</a></pre>
<pre><a href="https://github.com/Cuis-Smalltalk/Cuis-Smalltalk-Dev">https://github.com/Cuis-Smalltalk/Cuis-Smalltalk-Dev</a></pre>
<pre><a href="https://github.com/jvuletich">https://github.com/jvuletich</a></pre>
<pre><a href="https://www.linkedin.com/in/juan-vuletich-75611b3">https://www.linkedin.com/in/juan-vuletich-75611b3</a></pre>
<pre><a href="https://independent.academia.edu/JuanVuletich">https://independent.academia.edu/JuanVuletich</a></pre>
<pre><a href="https://www.researchgate.net/profile/Juan-Vuletich">https://www.researchgate.net/profile/Juan-Vuletich</a></pre>
<pre><a href="https://patents.justia.com/inventor/juan-manuel-vuletich">https://patents.justia.com/inventor/juan-manuel-vuletich</a></pre>
<pre><a href="https://twitter.com/JuanVuletich">https://twitter.com/JuanVuletich</a></pre>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New";color:black"><o:p> </o:p></span></p>
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