1 /* 2 * Copyright (c) 1983 Regents of the University of California. 3 * All rights reserved. The Berkeley software License Agreement 4 * specifies the terms and conditions for redistribution. 5 */ 6 7 #if defined(LIBC_SCCS) && !defined(lint) 8 static char sccsid[] = "@(#)inet_lnaof.c 5.3 (Berkeley) 10/01/87"; 9 #endif LIBC_SCCS and not lint 10 11 #include <sys/types.h> 12 #include <netinet/in.h> 13 14 /* 15 * Return the local network address portion of an 16 * internet address; handles class a/b/c network 17 * number formats. 18 */ 19 u_long 20 inet_lnaof(in) 21 struct in_addr in; 22 { 23 register u_long i = ntohl(in.s_addr); 24 25 if (IN_CLASSA(i)) 26 return ((i)&IN_CLASSA_HOST); 27 else if (IN_CLASSB(i)) 28 return ((i)&IN_CLASSB_HOST); 29 else 30 return ((i)&IN_CLASSC_HOST); 31 } 32