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Is gcc's __attribute__((packed)) / #pragma pack unsafe?

....h> #include <stddef.h> int main(void) { struct foo { char c; int x; } __attribute__((packed)); struct foo arr[2] = { { 'a', 10 }, {'b', 20 } }; int *p0 = &arr[0].x; int *p1 = &arr[1].x; printf("sizeof(struct foo) = %d\n", (int)sizeof(str...
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Regular expression to match URLs in Java

...ckzah|xxx)" + "|y[et]" + "|z[amw]))"; /** * Good characters for Internationalized Resource Identifiers (IRI). * This comprises most common used Unicode characters allowed in IRI * as detailed in RFC 3987. * Specifically, those two byte Unicode characters are ...
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How can strings be concatenated?

How to concatenate strings in python? 7 Answers 7 ...
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What is move semantics?

...: #include <cstring> #include <algorithm> class string { char* data; public: string(const char* p) { size_t size = std::strlen(p) + 1; data = new char[size]; std::memcpy(data, p, size); } Since we chose to manage the memory ourselves, we need...
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Why is the shovel operator (

...erators) which is an assignment. On the other hand << is an alias of concat() which alters the receiver in-place. share | improve this answer | follow | ...
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Forward an invocation of a variadic function in C

...t. See http://c-faq.com/varargs/handoff.html. Example: void myfun(const char *fmt, va_list argp) { vfprintf(stderr, fmt, argp); } share | improve this answer | follow...
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How to handle Objective-C protocols that contain properties?

...hInteger:(factor*amount)]; } // << @end int main(int argc, const char * argv[]) { @autoreleasepool { Person *duncan=[[Person alloc]initConforming]; duncan.firstname=@"Duncan"; duncan.lastname=@"Smith"; [Viewer printLargeDescription:duncan]; S...
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How to show a confirm message before delete?

...message on clicking delete (this maybe a button or an image). If the user selects ' Ok ' then delete is done, else if ' Cancel ' is clicked nothing happens. ...
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Why historically do people use 255 not 256 for database field magnitudes?

You often see database fields set to have a magnitude of 255 characters, what is the traditional / historic reason why? I assume it's something to do with paging / memory limits, and performance but the distinction between 255 and 256 has always confused me. ...
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what is the unsigned datatype?

... @Charles Bailey: these days - at least if you are being pragmatic rather than formal - long, int, short and char are considered to be different data types as they can be different sizes) with unsigned (and the default, signed)...