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How efficient is locking an unlocked mutex? What is the cost of a mutex?
...is really cheap. Unlocking mutex w/o contention is cheap too.
How much does a mutex cost? Is it a problem to have really a lot of mutexes? Or can I just throw as much mutex variables in my code as I have int variables and it doesn't really matter?
You can throw as much mutex variables into you...
Java 8: Lambda-Streams, Filter by Method with Exception
... can expect to get an IOException thrown in your face, even though collect does not declare it. In most, but not all real-life cases you would want to just rethrow the exception, anyway, and handle it as a generic failure. In all those cases, nothing is lost in clarity or correctness. Just beware of...
How to avoid the “divide by zero” error in SQL?
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If someone else doesn't instantly get why this works, NULLIF(d,0) will return NULL if d is 0. In SQL, dividing by NULL returns NULL. The Coalesce replaces the resulting NULL by 0.
– GuiSim
Apr 16 '14 at...
Is there a function to make a copy of a PHP array to another?
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@AndrewLarsson But PHP does that by default - That's the gist of it. References are not resolved though, so if you need that, you will have to recursively traverse the array and build a new one - Likewise, if the source array contains objects, and ...
SQL Server IN vs. EXISTS Performance
... and come up with any case where they don't get the same plan (though this does not apply to NOT IN and NOT EXISTS)
– Martin Smith
Apr 30 '19 at 12:17
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IE9 jQuery AJAX with CORS returns “Access is denied”
...ort this in core and is better suited as a plugin." (See this comment).
IE does not use the XMLHttpRequest, but an alternative object named XDomainRequest.
There is a plugin available to support this in jQuery, which can be found here:
https://github.com/jaubourg/ajaxHooks/blob/master/src/xdr.js
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how to make twitter bootstrap submenu to open on the left side?
... page and that menu has one more submenu. However, when submenu opens - it does not fit in the window and goes too much to the right, so that user can see only first letters. How to make that submenu to open not to the right, but to the left?
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How do I convert Word files to PDF programmatically? [closed]
...Application word = new Microsoft.Office.Interop.Word.Application();
// C# doesn't have optional arguments so we'll need a dummy value
object oMissing = System.Reflection.Missing.Value;
// Get list of Word files in specified directory
DirectoryInfo dirInfo = new DirectoryInfo(@"\\server\folder");
F...
Replace input type=file by an image
...ge).
I found some workaround here , and this interesting one too (but does not work on Chrome =/).
12 Answers
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Perform commands over ssh with Python
...'re using. That means you might design say a def run_cmd(host, cmd): which does what you want at first, but your needs evolve. You end up changing the helper for the new use case, which changes behavior of the older existing usage. Plan accordingly.
– Scott Prive
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