Pointers - Strings

Question

I have a code chunk which is quite meaningless for me. Is there someone can explain it to me?

Thanks

int strLength(char *str) {
char *p = str;
// Go until the end of the string
while (*p != ‘\0’)
p++;
return (p – str);
}

Firstly I dont get the idea behind return section of the code.

Secondly

char *p = str;

it didn't fit me perfectly

Thanks in Advance

Answer 1

The string is stored in memory sequentially, The idea is to find the character that ends the string (in C the accepted symbol is '\0'), you increment the pointer p until you find this symbol.

When you find '\0' , You substract between two addresses to find the length.