memset

 

C

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Defined in header <string.h>
void* memset( void* dest, int ch, 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.

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 <stdio.h>
#include <string.h>
 
int main(void)
{
    char str[] = "ghghghghghghghghghghgh";
    puts(str);
    memset(str,'a',5);
    puts(str);
    return 0;
}

Output:

ghghghghghghghghghghgh
aaaaahghghghghghghghgh

See also

memcpy	copies one buffer to another (function)
C++ documentation for memset