Replicate the standard string library function strlen().

#include <stdio.h>

int fnstrlen(char *);

int main(void)
{
char str[40];
int l;

printf("\nEnter a string : ");
gets(str);

l = fnstrlen(str);

printf("\nLength is %d", l);

return 0;
}

int fnstrlen(char *p)
{
int len;
for(len = 0 ; *p != '\0' ; p++)
{
len++;
}

return len;
}