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How do I use extern to share variables between source files?

... is demonstrated by file3.h, file1.c and file2.c: file3.h extern int global_variable; /* Declaration of the variable */ file1.c #include "file3.h" /* Declaration made available here */ #include "prog1.h" /* Function declarations */ /* Variable defined here */ int global_variable = 37; /* Def...
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How to fix Error: laravel.log could not be opened?

... OS. to figure out what's your web server user and group use the following commands. for nginx use: ps aux|grep nginx|grep -v grep for apache use: ps aux | egrep '(apache|httpd)' share | improve...
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Can I get CONST's defined on a PHP class?

...to looking at caching the result. <?php class Profile { const LABEL_FIRST_NAME = "First Name"; const LABEL_LAST_NAME = "Last Name"; const LABEL_COMPANY_NAME = "Company"; } $refl = new ReflectionClass('Profile'); print_r($refl->getConstants()); Output: Array ( 'LABEL_FIRST...
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Drop data frame columns by name

... @AjayOhri Yes, it would. Without a comma, you use the "list" way of selecting, which means that even when you extract a single column, you still get a data frame returned. If you use the "matrix" way, as you do, you should be aware that if you only select a si...
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Using Python String Formatting with Lists

...rmat with print() to iterate a list. How about this (python 3.x): sample_list = ['cat', 'dog', 'bunny', 'pig'] print("Your list of animals are: {}, {}, {} and {}".format(*sample_list)) Read the docs here on using format(). ...
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How to format a java.sql Timestamp for displaying?

...SQL and want the database itself to perform the conversion, use this: DATE_FORMAT(date,format) If you prefer to format using Java, use this: java.text.SimpleDateFormat SimpleDateFormat dateFormat = new SimpleDateFormat("M/dd/yyyy"); dateFormat.format( new Date() ); ...
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Where does gcc look for C and C++ header files?

...rog-name=cpp) -v (correctly) gives one more path, which is /usr/include/x86_64-linux-gnu – wlnirvana May 6 '16 at 15:10 3 ...
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Is there a performance difference between i++ and ++i in C++?

... this->data += 1; return *this; } Foo Foo::operator++(int ignored_dummy_value) // called for i++ { Foo tmp(*this); // variable "tmp" cannot be optimized away by the compiler ++(*this); return tmp; } Since the compiler isn't generating code, but just calling an operator++ ...
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How do I set bold and italic on UILabel of iPhone/iPad?

...t { return with([.traitBold, .traitItalic]) } func with(_ traits: UIFontDescriptor.SymbolicTraits...) -> UIFont { guard let descriptor = self.fontDescriptor.withSymbolicTraits(UIFontDescriptor.SymbolicTraits(traits).union(self.fontDescriptor.symbolicTraits)) else { ...
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How to avoid 'cannot read property of undefined' errors?

...tive "in", but allows paths. var testObject = {a: {b: {c: 'walrus'}}}; if(_.has(testObject, 'a.b.c')) { //Safely access your walrus here } share | improve this answer | f...