1 /* 2 * strncmp.c 3 */ 4 5 #include <string.h> 6 strncmp(const char * s1,const char * s2,size_t n)7int strncmp(const char *s1, const char *s2, size_t n) 8 { 9 const unsigned char *c1 = (const unsigned char *)s1; 10 const unsigned char *c2 = (const unsigned char *)s2; 11 unsigned char ch; 12 int d = 0; 13 14 while (n--) { 15 d = (int)(ch = *c1++) - (int)*c2++; 16 if (d || !ch) 17 break; 18 } 19 20 return d; 21 } 22