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C++ : why bool is 8 bits long?

... address of an object. The object doesn't have to store its own address. A char is typically 8 bits wide, enough to store any of 256 characters, but each char also has an address defined by where in memory it is located. That is why you can create a pointer to a char. – jalf ...
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Who architected / designed C++'s IOStreams, and would it still be considered well-designed by today'

...; operator will only read from the stream until it encounters a whitespace character, since there's no length information stored in the stream. So even though we output a string object containing "hello world", we're only going to input a string object containing "hello". So while the stream has s...
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iterating over each character of a String in ruby 1.8.6 (each_char)

I am new to ruby and currently trying to operate on each character separately from a base String in ruby. I am using ruby 1.8.6 and would like to do something like: ...
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How expensive is RTTI?

...ases with optimisation, typeid() is nearly x20 faster than dyncamic_cast. Chart The Code As requested in the comments, the code is below (a bit messy, but works). 'FastDelegate.h' is available from here. #include <iostream> #include "FastDelegate.h" #include "cycle.h" #include "time.h" // U...
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How to find all serial devices (ttyS, ttyUSB, ..) on Linux without opening them?

...t(devicedir.c_str(), &st)==0 && S_ISLNK(st.st_mode)) { char buffer[1024]; memset(buffer, 0, sizeof(buffer)); // Append '/driver' and return basename of the target devicedir += "/driver"; if (readlink(devicedir.c_str(), buffer, sizeof(buffer)) &gt...
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What does “Memory allocated at compile time” really mean?

...and (relative) position of this allocation is determined at compile time. char a[32]; char b; char c; Those 3 variables are "allocated at compile time", it means that the compiler calculates their size (which is fixed) at compile time. The variable a will be an offset in memory, let's say, pointi...
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When is CRC more appropriate to use than MD5/SHA1?

... inappropriate CRC hashes are for hash tables. It also explains the actual characteristics of the algorithm. The study also includes evaluation of other hash algorithms and is a good reference to keep. The relevant conclusion on CRC for hashes: CRC32 was never intended for hash table use. There...
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When should I use nil and NULL in Objective-C?

...ke a C pointer) in Objective-C. Like nil , NULL got no value nor address. char *myChar = NULL; struct MyStruct *dStruct = NULL; So if there is a situation, when I need to check my struct (structure type variable) is empty or not then, I will use: if (dStruct == NULL) NSLog("The struct is emp...
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How to set selected value of jquery select2?

This belong to codes prior to select2 version 4 28 Answers 28 ...
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How to parse a string to an int in C++?

What's the C++ way of parsing a string (given as char *) into an int? Robust and clear error handling is a plus (instead of returning zero ). ...