str_diff - compare two ASCIIZ strings

str_diff returns negative, 0, or positive, depending on whether the string a[0], a[1], ..., a[n]=='\0' is
       lexicographically smaller than, equal to, or greater than the string b[0], b[1], ..., b[m-1]=='\0'.

       If the strings are different, str_diff does not read bytes past the first difference.

       str_diff - compare two ASCIIZ strings

strlen(3)

                                                                                                     str_diff(3)

#include<libowfat/str.h>

       int str_diff(const char* a,const char* b);