std::memset

 

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Defined in header <cstring>
void* memset( void* dest, int ch, std::size_t count );

Copies the value static_cast<unsigned char>(ch) into each of the first count characters of the object pointed to by dest. If the object is a potentially-overlapping subobject or is not TriviallyCopyable (e.g., scalar, C-compatible struct, or an array of trivially copyable type), the behavior is undefined. If count is greater than the size of the object pointed to by dest, the behavior is undefined.