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if.c revision 1.48
      1 /*	$NetBSD: if.c,v 1.48 2001/04/06 05:10:28 itojun Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1983, 1988, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *	This product includes software developed by the University of
     18  *	California, Berkeley and its contributors.
     19  * 4. Neither the name of the University nor the names of its contributors
     20  *    may be used to endorse or promote products derived from this software
     21  *    without specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  */
     35 
     36 #include <sys/cdefs.h>
     37 #ifndef lint
     38 #if 0
     39 static char sccsid[] = "from: @(#)if.c	8.2 (Berkeley) 2/21/94";
     40 #else
     41 __RCSID("$NetBSD: if.c,v 1.48 2001/04/06 05:10:28 itojun Exp $");
     42 #endif
     43 #endif /* not lint */
     44 
     45 #include <sys/types.h>
     46 #include <sys/protosw.h>
     47 #include <sys/socket.h>
     48 
     49 #include <net/if.h>
     50 #include <net/if_dl.h>
     51 #include <net/if_types.h>
     52 #include <netinet/in.h>
     53 #include <netinet/in_var.h>
     54 #include <netns/ns.h>
     55 #include <netns/ns_if.h>
     56 #include <netiso/iso.h>
     57 #include <netiso/iso_var.h>
     58 #include <arpa/inet.h>
     59 
     60 #include <signal.h>
     61 #include <stdio.h>
     62 #include <stdlib.h>
     63 #include <string.h>
     64 #include <unistd.h>
     65 #include <netdb.h>
     66 
     67 #include "netstat.h"
     68 
     69 #define	YES	1
     70 #define	NO	0
     71 
     72 static void sidewaysintpr __P((u_int, u_long));
     73 static void catchalarm __P((int));
     74 
     75 /*
     76  * Print a description of the network interfaces.
     77  * NOTE: ifnetaddr is the location of the kernel global "ifnet",
     78  * which is a TAILQ_HEAD.
     79  */
     80 void
     81 intpr(interval, ifnetaddr, pfunc)
     82 	int interval;
     83 	u_long ifnetaddr;
     84 	void (*pfunc)(char *);
     85 {
     86 	struct ifnet ifnet;
     87 	union {
     88 		struct ifaddr ifa;
     89 		struct in_ifaddr in;
     90 #ifdef INET6
     91 		struct in6_ifaddr in6;
     92 #endif /* INET6 */
     93 		struct ns_ifaddr ns;
     94 		struct iso_ifaddr iso;
     95 	} ifaddr;
     96 	u_long ifaddraddr;
     97 	struct sockaddr *sa;
     98 	struct ifnet_head ifhead;	/* TAILQ_HEAD */
     99 	char name[IFNAMSIZ + 1];	/* + 1 for `*' */
    100 #ifdef INET6
    101 	char hbuf[NI_MAXHOST];		/* for getnameinfo() */
    102 #ifdef KAME_SCOPEID
    103 	const int niflag = NI_NUMERICHOST | NI_WITHSCOPEID;
    104 #else
    105 	const int niflag = NI_NUMERICHOST;
    106 #endif
    107 #endif
    108 
    109 	if (ifnetaddr == 0) {
    110 		printf("ifnet: symbol not defined\n");
    111 		return;
    112 	}
    113 	if (interval) {
    114 		sidewaysintpr((unsigned)interval, ifnetaddr);
    115 		return;
    116 	}
    117 
    118 	/*
    119 	 * Find the pointer to the first ifnet structure.  Replace
    120 	 * the pointer to the TAILQ_HEAD with the actual pointer
    121 	 * to the first list element.
    122 	 */
    123 	if (kread(ifnetaddr, (char *)&ifhead, sizeof ifhead))
    124 		return;
    125 	ifnetaddr = (u_long)ifhead.tqh_first;
    126 
    127 	if (!sflag & !pflag) {
    128 		if (bflag) {
    129 			printf("%-5.5s %-5.5s %-13.13s %-17.17s "
    130 			       "%10.10s %10.10s",
    131 			       "Name", "Mtu", "Network", "Address",
    132 			       "Ibytes", "Obytes");
    133 		} else {
    134 			printf("%-5.5s %-5.5s %-13.13s %-17.17s "
    135 			       "%8.8s %5.5s %8.8s %5.5s %5.5s",
    136 			       "Name", "Mtu", "Network", "Address", "Ipkts", "Ierrs",
    137 			       "Opkts", "Oerrs", "Colls");
    138 		}
    139 		if (tflag)
    140 			printf(" %4.4s", "Time");
    141 		if (dflag)
    142 			printf(" %5.5s", "Drops");
    143 		putchar('\n');
    144 	}
    145 	ifaddraddr = 0;
    146 	while (ifnetaddr || ifaddraddr) {
    147 		struct sockaddr_in *sin;
    148 #ifdef INET6
    149 		struct sockaddr_in6 *sin6;
    150 #endif /* INET6 */
    151 		char *cp;
    152 		int n, m;
    153 
    154 		if (ifaddraddr == 0) {
    155 			if (kread(ifnetaddr, (char *)&ifnet, sizeof ifnet))
    156 				return;
    157 			memmove(name, ifnet.if_xname, IFNAMSIZ);
    158 			name[IFNAMSIZ - 1] = '\0';	/* sanity */
    159 			ifnetaddr = (u_long)ifnet.if_list.tqe_next;
    160 			if (interface != 0 && strcmp(name, interface) != 0)
    161 				continue;
    162 			cp = strchr(name, '\0');
    163 
    164 			if (pfunc) {
    165 				(*pfunc)(name);
    166 				continue;
    167 			}
    168 
    169 			if ((ifnet.if_flags & IFF_UP) == 0)
    170 				*cp++ = '*';
    171 			*cp = '\0';
    172 			ifaddraddr = (u_long)ifnet.if_addrlist.tqh_first;
    173 		}
    174 		if (vflag)
    175 			n = strlen(name) < 5 ? 5 : strlen(name);
    176 		else
    177 			n = 5;
    178 		printf("%-*.*s %-5llu ", n, n, name,
    179 		    (unsigned long long)ifnet.if_mtu);
    180 		if (ifaddraddr == 0) {
    181 			printf("%-13.13s ", "none");
    182 			printf("%-17.17s ", "none");
    183 		} else {
    184 			char hexsep = '.';		/* for hexprint */
    185 			const char hexfmt[] = "%02x%c";	/* for hexprint */
    186 			if (kread(ifaddraddr, (char *)&ifaddr, sizeof ifaddr)) {
    187 				ifaddraddr = 0;
    188 				continue;
    189 			}
    190 #define CP(x) ((char *)(x))
    191 			cp = (CP(ifaddr.ifa.ifa_addr) - CP(ifaddraddr)) +
    192 				CP(&ifaddr); sa = (struct sockaddr *)cp;
    193 			switch (sa->sa_family) {
    194 			case AF_UNSPEC:
    195 				printf("%-13.13s ", "none");
    196 				printf("%-17.17s ", "none");
    197 				break;
    198 			case AF_INET:
    199 				sin = (struct sockaddr_in *)sa;
    200 #ifdef notdef
    201 				/*
    202 				 * can't use inet_makeaddr because kernel
    203 				 * keeps nets unshifted.
    204 				 */
    205 				in = inet_makeaddr(ifaddr.in.ia_subnet,
    206 					INADDR_ANY);
    207 				cp = netname(in.s_addr,
    208 					ifaddr.in.ia_subnetmask);
    209 #else
    210 				cp = netname(ifaddr.in.ia_subnet,
    211 					ifaddr.in.ia_subnetmask);
    212 #endif
    213 				if (vflag)
    214 					n = strlen(cp) < 13 ? 13 : strlen(cp);
    215 				else
    216 					n = 13;
    217 				printf("%-*.*s ", n, n, cp);
    218 				cp = routename(sin->sin_addr.s_addr);
    219 				if (vflag)
    220 					n = strlen(cp) < 17 ? 17 : strlen(cp);
    221 				else
    222 					n = 17;
    223 				printf("%-*.*s ", n, n, cp);
    224 				if (aflag) {
    225 					u_long multiaddr;
    226 					struct in_multi inm;
    227 
    228 					multiaddr = (u_long)
    229 					    ifaddr.in.ia_multiaddrs.lh_first;
    230 					while (multiaddr != 0) {
    231 						kread(multiaddr, (char *)&inm,
    232 						   sizeof inm);
    233 						printf("\n%25s %-17.17s ", "",
    234 						   routename(
    235 						      inm.inm_addr.s_addr));
    236 						multiaddr =
    237 						   (u_long)inm.inm_list.le_next;
    238 					}
    239 				}
    240 				break;
    241 #ifdef INET6
    242 			case AF_INET6:
    243 				sin6 = (struct sockaddr_in6 *)sa;
    244 #ifdef KAME_SCOPEID
    245 				if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) {
    246 					sin6->sin6_scope_id =
    247 						ntohs(*(u_int16_t *)
    248 						  &sin6->sin6_addr.s6_addr[2]);
    249 					/* too little width */
    250 					if (!vflag)
    251 						sin6->sin6_scope_id = 0;
    252 					sin6->sin6_addr.s6_addr[2] = 0;
    253 					sin6->sin6_addr.s6_addr[3] = 0;
    254 				}
    255 #endif
    256 				cp = netname6(&ifaddr.in6.ia_addr,
    257 					&ifaddr.in6.ia_prefixmask.sin6_addr);
    258 				if (vflag)
    259 					n = strlen(cp) < 13 ? 13 : strlen(cp);
    260 				else
    261 					n = 13;
    262 				printf("%-*.*s ", n, n, cp);
    263 				if (getnameinfo((struct sockaddr *)sin6,
    264 						sin6->sin6_len,
    265 						hbuf, sizeof(hbuf), NULL, 0,
    266 						niflag) != 0) {
    267 					cp = "?";
    268 				} else
    269 					cp = hbuf;
    270 				if (vflag)
    271 					n = strlen(cp) < 17 ? 17 : strlen(cp);
    272 				else
    273 					n = 17;
    274 				printf("%-*.*s ", n, n, cp);
    275 				if (aflag) {
    276 					u_long multiaddr;
    277 					struct in6_multi inm;
    278 					struct sockaddr_in6 sin6;
    279 
    280 					multiaddr = (u_long)
    281 					    ifaddr.in6.ia6_multiaddrs.lh_first;
    282 					while (multiaddr != 0) {
    283 						kread(multiaddr, (char *)&inm,
    284 						   sizeof inm);
    285 						memset(&sin6, 0, sizeof(sin6));
    286 						sin6.sin6_len = sizeof(struct sockaddr_in6);
    287 						sin6.sin6_family = AF_INET6;
    288 						sin6.sin6_addr = inm.in6m_addr;
    289 						sin6.sin6_scope_id =
    290 						    ntohs(*(u_int16_t *)
    291 							&sin6.sin6_addr.s6_addr[2]);
    292 						sin6.sin6_addr.s6_addr[2] = 0;
    293 						sin6.sin6_addr.s6_addr[3] = 0;
    294 						if (getnameinfo((struct sockaddr *)&sin6,
    295 						    sin6.sin6_len, hbuf,
    296 						    sizeof(hbuf), NULL, 0,
    297 						    niflag) != 0) {
    298 							strlcpy(hbuf, "??",
    299 							    sizeof(hbuf));
    300 						}
    301 						cp = hbuf;
    302 						if (vflag)
    303 						    n = strlen(cp) < 17
    304 							? 17 : strlen(cp);
    305 						else
    306 						    n = 17;
    307 						printf("\n%25s %-*.*s ", "",
    308 						    n, n, cp);
    309 						multiaddr =
    310 						   (u_long)inm.in6m_entry.le_next;
    311 					}
    312 				}
    313 				break;
    314 #endif /*INET6*/
    315 #ifndef SMALL
    316 			case AF_APPLETALK:
    317 				printf("atalk:%-7.7s ",
    318 				       atalk_print(sa,0x10));
    319 				printf("%-17.17s ", atalk_print(sa,0x0b));
    320 				break;
    321 			case AF_NS:
    322 				{
    323 				struct sockaddr_ns *sns =
    324 					(struct sockaddr_ns *)sa;
    325 				u_long net;
    326 				char netnum[8];
    327 
    328 				*(union ns_net *)&net = sns->sns_addr.x_net;
    329 				(void)snprintf(netnum, sizeof(netnum), "%xH",
    330 				    (u_int32_t)ntohl(net));
    331 				upHex(netnum);
    332 				printf("ns:%-10s ", netnum);
    333 				printf("%-17.17s ",
    334 				    ns_phost((struct sockaddr *)sns));
    335 				}
    336 				break;
    337 #endif
    338 			case AF_LINK:
    339 				{
    340 				struct sockaddr_dl *sdl =
    341 					(struct sockaddr_dl *)sa;
    342 				    cp = (char *)LLADDR(sdl);
    343 				    if (sdl->sdl_type == IFT_FDDI
    344 					|| sdl->sdl_type == IFT_ETHER
    345 					|| sdl->sdl_type == IFT_IEEE1394)
    346 					    hexsep = ':';
    347 				    n = sdl->sdl_alen;
    348 				    if (sdl->sdl_type == IFT_IEEE1394
    349 					&& sdl->sdl_len > 8)
    350 					    n = 8; /* XXX */
    351 				}
    352 				m = printf("%-13.13s ", "<Link>");
    353 				goto hexprint;
    354 			default:
    355 				m = printf("(%d)", sa->sa_family);
    356 				for (cp = sa->sa_len + (char *)sa;
    357 					--cp > sa->sa_data && (*cp == 0);) {}
    358 				n = cp - sa->sa_data + 1;
    359 				cp = sa->sa_data;
    360 			hexprint:
    361 				while (--n >= 0)
    362 					m += printf(hexfmt, *cp++ & 0xff,
    363 						    n > 0 ? hexsep : ' ');
    364 				m = 32 - m;
    365 				while (m-- > 0)
    366 					putchar(' ');
    367 				break;
    368 			}
    369 			ifaddraddr = (u_long)ifaddr.ifa.ifa_list.tqe_next;
    370 		}
    371 		if (bflag) {
    372 			printf("%10llu %10llu",
    373 				(unsigned long long)ifnet.if_ibytes,
    374 				(unsigned long long)ifnet.if_obytes);
    375 		} else {
    376 			printf("%8llu %5llu %8llu %5llu %5llu",
    377 				(unsigned long long)ifnet.if_ipackets,
    378 				(unsigned long long)ifnet.if_ierrors,
    379 				(unsigned long long)ifnet.if_opackets,
    380 				(unsigned long long)ifnet.if_oerrors,
    381 				(unsigned long long)ifnet.if_collisions);
    382 		}
    383 		if (tflag)
    384 			printf(" %4d", ifnet.if_timer);
    385 		if (dflag)
    386 			printf(" %5d", ifnet.if_snd.ifq_drops);
    387 		putchar('\n');
    388 	}
    389 }
    390 
    391 #define	MAXIF	100
    392 struct	iftot {
    393 	char ift_name[IFNAMSIZ];	/* interface name */
    394 	u_quad_t ift_ip;		/* input packets */
    395 	u_quad_t ift_ib;		/* input bytes */
    396 	u_quad_t ift_ie;		/* input errors */
    397 	u_quad_t ift_op;		/* output packets */
    398 	u_quad_t ift_ob;		/* output bytes */
    399 	u_quad_t ift_oe;		/* output errors */
    400 	u_quad_t ift_co;		/* collisions */
    401 	int ift_dr;			/* drops */
    402 } iftot[MAXIF];
    403 
    404 u_char	signalled;			/* set if alarm goes off "early" */
    405 
    406 /*
    407  * Print a running summary of interface statistics.
    408  * Repeat display every interval seconds, showing statistics
    409  * collected over that interval.  Assumes that interval is non-zero.
    410  * First line printed at top of screen is always cumulative.
    411  */
    412 static void
    413 sidewaysintpr(interval, off)
    414 	unsigned interval;
    415 	u_long off;
    416 {
    417 	struct ifnet ifnet;
    418 	u_long firstifnet;
    419 	struct iftot *ip, *total;
    420 	int line;
    421 	struct iftot *lastif, *sum, *interesting;
    422 	struct ifnet_head ifhead;	/* TAILQ_HEAD */
    423 	int oldmask;
    424 
    425 	/*
    426 	 * Find the pointer to the first ifnet structure.  Replace
    427 	 * the pointer to the TAILQ_HEAD with the actual pointer
    428 	 * to the first list element.
    429 	 */
    430 	if (kread(off, (char *)&ifhead, sizeof ifhead))
    431 		return;
    432 	firstifnet = (u_long)ifhead.tqh_first;
    433 
    434 	lastif = iftot;
    435 	sum = iftot + MAXIF - 1;
    436 	total = sum - 1;
    437 	interesting = (interface == NULL) ? iftot : NULL;
    438 	for (off = firstifnet, ip = iftot; off;) {
    439 		if (kread(off, (char *)&ifnet, sizeof ifnet))
    440 			break;
    441 		memset(ip->ift_name, 0, sizeof(ip->ift_name));
    442 		snprintf(ip->ift_name, IFNAMSIZ, "%s", ifnet.if_xname);
    443 		if (interface && strcmp(ifnet.if_xname, interface) == 0)
    444 			interesting = ip;
    445 		ip++;
    446 		if (ip >= iftot + MAXIF - 2)
    447 			break;
    448 		off = (u_long)ifnet.if_list.tqe_next;
    449 	}
    450 	if (interesting == NULL) {
    451 		fprintf(stderr, "%s: %s: unknown interface\n",
    452 		    getprogname(), interface);
    453 		exit(1);
    454 	}
    455 	lastif = ip;
    456 
    457 	(void)signal(SIGALRM, catchalarm);
    458 	signalled = NO;
    459 	(void)alarm(interval);
    460 banner:
    461 	if (bflag)
    462 		printf("%7.7s in %8.8s %6.6s out %5.5s",
    463 		    interesting->ift_name, " ",
    464 		    interesting->ift_name, " ");
    465 	else
    466 		printf("%5.5s in %5.5s%5.5s out %5.5s %5.5s",
    467 		    interesting->ift_name, " ",
    468 		    interesting->ift_name, " ", " ");
    469 	if (dflag)
    470 		printf(" %5.5s", " ");
    471 	if (lastif - iftot > 0) {
    472 		if (bflag)
    473 			printf("  %7.7s in %8.8s %6.6s out %5.5s",
    474 			    "total", " ", "total", " ");
    475 		else
    476 			printf("  %5.5s in %5.5s%5.5s out %5.5s %5.5s",
    477 			    "total", " ", "total", " ", " ");
    478 		if (dflag)
    479 			printf(" %5.5s", " ");
    480 	}
    481 	for (ip = iftot; ip < iftot + MAXIF; ip++) {
    482 		ip->ift_ip = 0;
    483 		ip->ift_ib = 0;
    484 		ip->ift_ie = 0;
    485 		ip->ift_op = 0;
    486 		ip->ift_ob = 0;
    487 		ip->ift_oe = 0;
    488 		ip->ift_co = 0;
    489 		ip->ift_dr = 0;
    490 	}
    491 	putchar('\n');
    492 	if (bflag)
    493 		printf("%10.10s %8.8s %10.10s %5.5s",
    494 		    "bytes", " ", "bytes", " ");
    495 	else
    496 		printf("%8.8s %5.5s %8.8s %5.5s %5.5s",
    497 		    "packets", "errs", "packets", "errs", "colls");
    498 	if (dflag)
    499 		printf(" %5.5s", "drops");
    500 	if (lastif - iftot > 0) {
    501 		if (bflag)
    502 			printf("  %10.10s %8.8s %10.10s %5.5s",
    503 			    "bytes", " ", "bytes", " ");
    504 		else
    505 			printf("  %8.8s %5.5s %8.8s %5.5s %5.5s",
    506 			    "packets", "errs", "packets", "errs", "colls");
    507 		if (dflag)
    508 			printf(" %5.5s", "drops");
    509 	}
    510 	putchar('\n');
    511 	fflush(stdout);
    512 	line = 0;
    513 loop:
    514 	sum->ift_ip = 0;
    515 	sum->ift_ib = 0;
    516 	sum->ift_ie = 0;
    517 	sum->ift_op = 0;
    518 	sum->ift_ob = 0;
    519 	sum->ift_oe = 0;
    520 	sum->ift_co = 0;
    521 	sum->ift_dr = 0;
    522 	for (off = firstifnet, ip = iftot; off && ip < lastif; ip++) {
    523 		if (kread(off, (char *)&ifnet, sizeof ifnet)) {
    524 			off = 0;
    525 			continue;
    526 		}
    527 		if (ip == interesting) {
    528 			if (bflag) {
    529 				printf("%10llu %8.8s %10llu %5.5s",
    530 				    (unsigned long long)(ifnet.if_ibytes -
    531 					ip->ift_ib), " ",
    532 				    (unsigned long long)(ifnet.if_obytes -
    533 					ip->ift_ob), " ");
    534 			} else {
    535 				printf("%8llu %5llu %8llu %5llu %5llu",
    536 				    (unsigned long long)
    537 					(ifnet.if_ipackets - ip->ift_ip),
    538 				    (unsigned long long)
    539 					(ifnet.if_ierrors - ip->ift_ie),
    540 				    (unsigned long long)
    541 					(ifnet.if_opackets - ip->ift_op),
    542 				    (unsigned long long)
    543 					(ifnet.if_oerrors - ip->ift_oe),
    544 				    (unsigned long long)
    545 					(ifnet.if_collisions - ip->ift_co));
    546 			}
    547 			if (dflag)
    548 				printf(" %5llu",
    549 				    (unsigned long long)
    550 					(ifnet.if_snd.ifq_drops - ip->ift_dr));
    551 		}
    552 		ip->ift_ip = ifnet.if_ipackets;
    553 		ip->ift_ib = ifnet.if_ibytes;
    554 		ip->ift_ie = ifnet.if_ierrors;
    555 		ip->ift_op = ifnet.if_opackets;
    556 		ip->ift_ob = ifnet.if_obytes;
    557 		ip->ift_oe = ifnet.if_oerrors;
    558 		ip->ift_co = ifnet.if_collisions;
    559 		ip->ift_dr = ifnet.if_snd.ifq_drops;
    560 		sum->ift_ip += ip->ift_ip;
    561 		sum->ift_ib += ip->ift_ib;
    562 		sum->ift_ie += ip->ift_ie;
    563 		sum->ift_op += ip->ift_op;
    564 		sum->ift_ob += ip->ift_ob;
    565 		sum->ift_oe += ip->ift_oe;
    566 		sum->ift_co += ip->ift_co;
    567 		sum->ift_dr += ip->ift_dr;
    568 		off = (u_long)ifnet.if_list.tqe_next;
    569 	}
    570 	if (lastif - iftot > 0) {
    571 		if (bflag) {
    572 			printf("  %10llu %8.8s %10llu %5.5s",
    573 			    (unsigned long long)
    574 				(sum->ift_ib - total->ift_ib), " ",
    575 			    (unsigned long long)
    576 				(sum->ift_ob - total->ift_ob), " ");
    577 		} else {
    578 			printf("  %8llu %5llu %8llu %5llu %5llu",
    579 			    (unsigned long long)
    580 				(sum->ift_ip - total->ift_ip),
    581 			    (unsigned long long)
    582 				(sum->ift_ie - total->ift_ie),
    583 			    (unsigned long long)
    584 				(sum->ift_op - total->ift_op),
    585 			    (unsigned long long)
    586 				(sum->ift_oe - total->ift_oe),
    587 			    (unsigned long long)
    588 				(sum->ift_co - total->ift_co));
    589 		}
    590 		if (dflag)
    591 			printf(" %5llu",
    592 			    (unsigned long long)(sum->ift_dr - total->ift_dr));
    593 	}
    594 	*total = *sum;
    595 	putchar('\n');
    596 	fflush(stdout);
    597 	line++;
    598 	oldmask = sigblock(sigmask(SIGALRM));
    599 	if (! signalled) {
    600 		sigpause(0);
    601 	}
    602 	sigsetmask(oldmask);
    603 	signalled = NO;
    604 	(void)alarm(interval);
    605 	if (line == 21)
    606 		goto banner;
    607 	goto loop;
    608 	/*NOTREACHED*/
    609 }
    610 
    611 /*
    612  * Called if an interval expires before sidewaysintpr has completed a loop.
    613  * Sets a flag to not wait for the alarm.
    614  */
    615 static void
    616 catchalarm(signo)
    617 	int signo;
    618 {
    619 
    620 	signalled = YES;
    621 }
    622