I've come to bother you all with another probably really simple C question.
Using the following code:
int get_len(char *string){
printf("len: %lu\n", strlen(string));
return 0;
}
int main(){
char *x = "test";
char y[4] = {'t','e','s','t'};
get_len(x); // len: 4
get_len(y); // len: 6
return 0;
}
2 questions. Why are they different and why is y 6? Thanks guys.
EDIT: Sorry, I know what would fix it, I kind of just wanted to understand what was going on. So does strlen just keep forwarding the point till it happens to find a \0? Also when I did strlen in the main function instead of in the get_len function both were 4. Was that just a coincidence?
Answer
y is not null-terminated. strlen() counts characters until it hits a null character. Yours happened to find one after 6, but it could be any number. Try this:
char y[] = {'t','e','s','t', '\0'};
Here's what an implementation of strlen() might look like (off the top of my head -- don't have my K&R book handy, but I believe there's an implementation given there):
size_t strlen(const char* s)
{
size_t result = 0;
while (*s++) ++result;
return result;
}