KwCheng's blog

memset ( void * ptr, int value, size_t num ) , 可以讓我們對pointer所指向的一個記憶體空間塞入資料 , 

在memset中主要有三個參數 , 分別是:

  ptr : Pointer to the block of memory to fill.

  value : Value to be set. The value is passed as an int, but the function fills the block of memory using the unsigned char conversion of this value.

  num : Number of bytes to be set to the value.

  for example : 

#include <stdio.h> 

#include <string.h> 

int main () 

{ 

char str[] = "almost every programmer should know memset!"; 

memset (str,'-',6); 

puts (str);

return 0; 

}

 我們可以看到memset幫我們在str所指向的記憶體空間中塞入了6個'-' .

ref : http://www.cplusplus.com/reference/clibrary/cstring/memset/