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Is errno thread-safe?
...t errno; so my question is, is it safe to check errno value after some calls or use perror() in multi-threaded code. Is this a thread safe variable? If not, then whats the alternative ?
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Is there a benefit to defining a class inside another class in Python?
What I'm talking about here are nested classes. Essentially, I have two classes that I'm modeling. A DownloadManager class and a DownloadThread class. The obvious OOP concept here is composition. However, composition doesn't necessarily mean nesting, right?
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Is it intended by the C++ standards committee that in C++11 unordered_map destroys what it inserts?
... always move from its argument. It's supposed to move if the argument is really an rvalue, and copy if it's an lvalue.
The behaviour, you observe, which always moves, is a bug in libstdc++, which is now fixed according to a comment on the question. For those curious, I took a look at the g++-4.8 he...
Unzip a file with php
...e it out by yourself. On the other hand, the fact that this code could actually be published online somewhere as the correct way to unzip a file is a bit frightening.
PHP has built-in extensions for dealing with compressed files. There should be no need to use system calls for this. ZipArchivedocs ...
relative path in require_once doesn't work
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Note that you should manually include the trailing slash in after __DIR__. So: require_once(__DIR__.'/../class/user.php'); Per the documentation, the trailing slash is omitted except for the root directory.
– Ariel Allon
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When to use enumerateObjectsUsingBlock vs. for
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Ultimately, use whichever pattern you want to use and comes more naturally in the context.
While for(... in ...) is quite convenient and syntactically brief, enumerateObjectsUsingBlock: has a number of features that may or may not prove interesting:
enumerateObjectsUsingBlock: will be as fas...
Setting the selected value on a Django forms.ChoiceField
...rying to assign the selected value to a ChoiceField.
If you have already called super().__init__ in your Form class, you should update the form.initial dictionary, not the field.initial property. If you study form.initial (e.g. print self.initial after the call to super().__init__), it will contai...
Express-js can't GET my static files, why?
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In case of new install you should verify that your express module is properly installed (expressjs.com/en/starter/installing.html) then you should check the path and your directory name like Giacomo said ;)
– Spl2nky
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How does _gaq.push(['_trackPageLoadTime']) work?
...precated and its functionality has been set as a default setting. (Functionally speaking, it has gone from being an opt-in feature to being an opt-out feature.)
_setSiteSpeedSampleRate is the new function for setting the sample rate on this feature; its default value is 1 (as in 1%). To opt out of ...
Add custom messages in assert?
...rk; they’re compile-time constants and their use in this context is trivially optimized away. There is no runtime cost.
– zneak
Aug 9 '19 at 8:46
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