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Are there any downsides to passing structs by value in C, rather than passing a pointer?

... For small structs (eg point, rect) passing by value is perfectly acceptable. But, apart from speed, there is one other reason why you should be careful passing/returning large structs by value: Stack space. A lot of C programming ...
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Using the “animated circle” in an ImageView while loading stuff

...inate="true" /> </RelativeLayout> And when you finish loading, call this one line: findViewById(R.id.loadingPanel).setVisibility(View.GONE); The result (and it spins too): share | i...
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Table header to stay fixed at the top when user scrolls it out of view with jQuery

... container other than window. mkoryak.github.io/floatThead has a more generally-applicable solution. – Yuck Nov 30 '13 at 19:42 13 ...
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PHP DOMDocument errors/warnings on html5-tags

... @SuperCat It's all dependant on the underlying libxml library. – lonesomeday Jul 2 '17 at 12:59 6 ...
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Is the sizeof(some pointer) always equal to four?

... Pointers to member functions are a real pain. It is unfortunate that not all compilers does it like the Digital Mars C++ compiler, which return 4 in all cases. – dalle Feb 18 '09 at 15:21 ...
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Determine device (iPhone, iPod Touch) with iOS

... @AnilSivadas: UI_USER_INTERFACE_IDIOM() is safe to use in apps that still support iOS < 3.2: it is a macro in UIDevice.h specifically written to default to UIUserInterfaceIdiomPhone on such older iOS versions. – mkle...
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Smart pointers: who owns the object? [closed]

C++ is all about memory ownership - aka ownership semantics . 11 Answers 11 ...
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PSQLException: current transaction is aborted, commands ignored until end of transaction block

...gnored as a failed SQL statement. You are welcome to fail SQL statements all you want and PostgreSQL won't stop you. Stay being in a transaction, but when you detect that the first SQL has failed, either rollback/re-start or commit/restart the transaction. Then you can continue failing as many S...
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How do I check if file exists in jQuery or pure JavaScript?

...n('HEAD', url, false); http.send(); return http.status!=404; } Small changes and it could check for status HTTP status code 200 (success), instead. EDIT 2: Since sync XMLHttpRequest is deprecated, you can add a utility method like this to do it async: function executeIfFileExist(src, cal...
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Safe (bounds-checked) array lookup in Swift, through optional bindings?

... WARNING! Checking arrays this way can be really expensive. The contains method will iterate through all indices thus making this an O(n). A better way is to use the index and count to check the bounds. – Stefan Vasiljevic May 7 '...