C Language Strings Zeroing out a string
Example
You can call memset to zero out a string (or any other memory block).
Where str is the string to zero out, and n is the number of bytes in the string.
#include <stdlib.h> /* For EXIT_SUCCESS */
#include <stdio.h>
#include <string.h>
int main(void)
{
char str[42] = "fortytwo";
size_t n = sizeof str; /* Take the size not the length. */
printf("'%s'\n", str);
memset(str, '\0', n);
printf("'%s'\n", str);
return EXIT_SUCCESS;
}
Prints:
'fortytwo'
''
Another example:
#include <stdlib.h> /* For EXIT_SUCCESS */
#include <stdio.h>
#include <string.h>
#define FORTY_STR "forty"
#define TWO_STR "two"
int main(void)
{
char str[42] = FORTY_STR TWO_STR;
size_t n = sizeof str; /* Take the size not the length. */
char * point_to_two = strstr(str, TWO_STR);
printf("'%s'\n", str);
memset(point_to_two, '\0', n);
printf("'%s'\n", str);
memset(str, '\0', n);
printf("'%s'\n", str);
return EXIT_SUCCESS;
}
Prints:
'fortytwo'
'forty'
''
