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How to get default gateway in Mac OSX

...sult thus looks like this: 192.168.195.1 In this case, netstat displays all result, grep only selects the line with 'default' in it, and awk further matches the pattern to display the second column in the text. You can similarly use route -n get default command to get the required result. The fu...
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Using an if statement to check if a div is empty

...If a container has a very long HTML content? – techie_28 Jun 17 '16 at 10:07 add a comment  |  ...
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What is thread safe or non-thread safe in PHP?

...s implement different techniques for handling incoming HTTP requests in parallel. A pretty popular technique is using threads -- that is, the web server will create/dedicate a single thread for each incoming request. The Apache HTTP web server supports multiple models for handling requests, one of w...
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Which way is best for creating an object in JavaScript? Is `var` necessary before an object property

...your example, Person (you should start the name with a capital letter) is called the constructor function. This is similar to classes in other OO languages. Use way 2 if you only need one object of a kind (like a singleton). If you want this object to inherit from another one, then you have to use a...
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How do I test which class an object is in Objective-C?

...ingFromClass([yourObject class]); or c-function from objective-c runtime api: #import <objc/runtime.h> /* ... */ const char* className = class_getName([yourObject class]); NSLog(@"yourObject is a: %s", className); EDIT: In Swift if touch.view is UIPickerView { // touch.view is of t...
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Can't open config file: /usr/local/ssl/openssl.cnf on Windows [duplicate]

... The solution is running this command: set OPENSSL_CONF=C:\OpenSSL-Win32\bin\openssl.cfg or set OPENSSL_CONF=[path-to-OpenSSL-install-dir]\bin\openssl.cfg in the command prompt before using openssl command. Let openssl know for sure where to find its .cfg file. Al...
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How to write :hover condition for a:before and a:after?

... This depends on what you're actually trying to do. If you simply wish to apply styles to a :before pseudo-element when the a element matches a pseudo-class, you need to write a:hover:before or a:visited:before instead. Notice the pseudo-element comes after ...
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Set value to NULL in MySQL

... can be inserted/updated without quotes: INSERT INTO user (name, something_optional) VALUES ("Joe", NULL); UPDATE user SET something_optional = NULL; share | improve this answer | ...
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C# code to validate email address

...e-mail addresses are more forgiving than you might first assume. These are all perfectly valid forms: cog@wheel "cogwheel the orange"@example.com 123@$.xyz For most use cases, a false "invalid" is much worse for your users and future proofing than a false "valid". Here's an article that used to ...
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Is it Linq or Lambda?

... This is LINQ (using query syntax): var _Results = from item in _List where item.Value == 1 select item; This is also LINQ (using method syntax): var _Results = _List.Where(x => x.Value == 1); It's interesting to note that bo...