

#include <strings.h>
int bcmp(const void * s1 , const void * s2 , size_t n );
The bcmp () function compares the two byte sequences s1 and s2 of length n each. If they are equal, and in particular if n is zero, bcmp () returns 0. Otherwise it returns a nonzero result.
The bcmp () function returns 0 if the byte sequences are equal, otherwise a nonzero result is returned.
4.3BSD. This function is deprecated (marked as LEGACY in POSIX.1-2001): use memcmp (3) in new programs.
memcmp (3) strcasecmp (3) strcmp (3) strcoll (3) strncasecmp (3) strncmp (3)