std::memset

 

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

Converts the value ch to unsigned char and copies it into each of the first count characters of the object pointed to by dest. If the object is not trivially-copyable (e.g., scalar, array, or a C-compatible struct), the behavior is undefined. If count is greater than the size of the object pointed to by dest, the behavior is undefined.

Parameters

dest	-	pointer to the object to fill
ch	-	fill byte
count	-	number of bytes to fill

Return value

dest

Example

Run this code

#include <iostream>
#include <cstring>
 
int main()
{
    int a[20];
    std::memset(a, 0, sizeof(a));
    for (int ai : a) std::cout << ai;
}

Output:

00000000000000000000

See also

memcpy	copies one buffer to another (function)
fill_n	assigns a value to a number of elements (function template)
is_trivially_copyable (C++11)	checks if a type is trivially copyable (class template)
C documentation for memset