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Is there a Unix utility to prepend timestamps to stdin?

... Could try using awk: <command> | awk '{ print strftime("%Y-%m-%d %H:%M:%S"), $0; fflush(); }' You may need to make sure that <command> produces line buffered output, i.e. it flushes its output stream after each line; the timestamp awk adds ...
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Calculate size of Object in Java [duplicate]

... an object takes up for a project (I'm comparing sizes of data structures) and it seems like there is no method to do this in Java. Supposedly, C/C++ has sizeOf() method, but this is nonexistant in Java. I tried recording the free memory in the JVM with Runtime.getRuntime().freeMemory() before a...
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setMaxResults for Spring-Data-JPA annotation?

...ata JPA 1.7.0 (Evans release train). You can use the newly introduced Top and First keywords that allow you to define query methods like this: findTop10ByLastnameOrderByFirstnameAsc(String lastname); Spring Data will automatically limit the results to the number you defined (defaulting to 1 if o...
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What's the @ in front of a string in C#?

...string verbatim = @"foo\bar"; string regular = "foo\\bar"; Here verbatim and regular have the same contents. It also allows multi-line contents - which can be very handy for SQL: string select = @" SELECT Foo FROM Bar WHERE Name='Baz'"; The one bit of escaping which is necessary for verbatim s...
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How can I get the MAC and the IP address of a connected client in PHP?

I need to know the MAC and the IP address of the connect clients, how can I do this in PHP? 16 Answers ...
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Is It Possible to Sandbox JavaScript Running In the Browser?

I'm wondering if it's possible to sandbox JavaScript running in the browser to prevent access to features that are normally available to JavaScript code running in an HTML page. ...
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Difference between two lists

...Using Except is exactly the right way to go. If your type overrides Equals and GetHashCode, or you're only interested in reference type equality (i.e. two references are only "equal" if they refer to the exact same object), you can just use: var list3 = list1.Except(list2).ToList(); If you need t...
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How can I parse a JSON file with PHP? [duplicate]

...array. Plus, the entire thing is capsuled in OOP, so you have better reuse and you can easily mock it in UnitTests plus you can stack Iterators with other iterators doing different things, like limiting, caching, filtering and so on.. in addition to any custom iterators you might want to create. ...
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Should arrays be used in C++?

Since std::list and std::vector exist, is there a reason to use traditional C arrays in C++, or should they be avoided, just like malloc ? ...
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Convert RGB to RGBA over white

... Take the lowest color component, and convert that to an alpha value. Then scale the color components by subtracting the lowest, and dividing by the alpha value. Example: 152 converts to an alpha value of (255 - 152) / 255 ~ 0.404 152 scales using (152 - 1...