lib/memcmp.c

   1 /* memcmp.c -- compare memory.
   2    Return:
   3    <0 if S1 < S2,
   4    0 if strings are identical,
   5    >0 if S1 > S2.
   6    Stops looking after N characters.  Doesn't stop at nulls.
   7    In the public domain.
   8    By David MacKenzie <djm@gnu.ai.mit.edu>. */
   9
  10 #include <sys/types.h>
  11
  12 int
  13 #if __STDC__
  14 memcmp (void const *v1, void const *v2, size_t n)
  15 {
  16   register char *s1 = (char *) v1, *s2 = (char *) v2;
  17 #else
  18 memcmp (s1, s2, n)
  19      register char *s1, *s2;
  20      register unsigned n;
  21 {
  22 #endif
  23   register int diff;
  24
  25   while (n--)
  26     {
  27       diff = *s1++ - *s2++;
  28       if (diff)
  29         return diff;
  30     }
  31   return 0;
  32 }