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How to write a large buffer into a binary file in C++, fast?

...es 2-5%. Thanks a lot to everyone. Update: 5 years have passed it's 2017 now. Compilers, hardware, libraries and my requirements have changed. That's why I made some changes to the code and did some new measurements. First up the code: #include <fstream> #include <chrono> #include &l...
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How do I upgrade my ruby 1.9.2-p0 to the latest patch level using rvm?

...sk RVM to list the ruby versions available to install by running rvm list known. In the output you should now see: # MRI Rubies ... [ruby-]1.9.2[-p320] ... The square brackets around the patch level indicate that this is currently RVM's default patch level for ruby 1.9.2. Finally, to install th...
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C++ Returning reference to local variable

...dies, making the reference returned from the function worthless because it now refers to an object that doesn't exist. int main() { int& p = func1(); /* p is garbage */ } The second version does work because the variable is allocated on the free store, which is not bound to the lifeti...
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Asynchronous shell exec in PHP

...ally starting an independent process. <?php `echo "the command"|at now`; ?> share | improve this answer | follow | ...
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What is a race condition?

...read scheduling algorithm can swap between threads at any time, you don't know the order in which the threads will attempt to access the shared data. Therefore, the result of the change in data is dependent on the thread scheduling algorithm, i.e. both threads are "racing" to access/change the data....
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Why do people put code like “throw 1; ” and “for(;;);” in front of json responses? [du

...Chrome (5) are still vulnerable to this. Another attack that all browsers now disallow was to redefine constructor functions: Array= function() { alert('I steal '+this); }; [1, 2, 3] And for now, IE8's implementation of properties (based on the ECMAScript Fifth Edition standard and Object.d...
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What's the difference between passing by reference vs. passing by value?

...by value vs. pass by reference" distinction as defined in the CS theory is now obsolete because the technique originally defined as "pass by reference" has since fallen out of favor and is seldom used now.1 Newer languages2 tend to use a different (but similar) pair of techniques to achieve the sam...
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What is the official “preferred” way to install pip and virtualenv systemwide?

... If you can install the latest Python (2.7.9 and up) Pip is now bundled with it. See: https://docs.python.org/2.7//installing/index.html If not : Update (from the release notes): Beginning with v1.5.1, pip does not require setuptools prior to running get-pip.py. Additionally, if ...
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iPhone UIView Animation Best Practice

...ify an arbitrary CoreImage filter to use as a transition, but as it stands now you can't do this on the iPhone, which lacks CoreImage. share | improve this answer | follow ...
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Loop through a date range with JavaScript

...ng around with milliseconds. Daylight savings aren't an issue either. var now = new Date(); var daysOfYear = []; for (var d = new Date(2012, 0, 1); d <= now; d.setDate(d.getDate() + 1)) { daysOfYear.push(new Date(d)); } Note that if you want to store the date, you'll need to make a new one...