xref: /freebsd/usr.bin/netstat/if.c (revision 99e8005137088aafb1350e23b113d69b01b0820f)
1 /*
2  * Copyright (c) 1983, 1988, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 /*
36 static char sccsid[] = "@(#)if.c	8.3 (Berkeley) 4/28/95";
37 */
38 static const char rcsid[] =
39   "$FreeBSD$";
40 #endif /* not lint */
41 
42 #include <sys/types.h>
43 #include <sys/protosw.h>
44 #include <sys/socket.h>
45 #include <sys/sysctl.h>
46 #include <sys/time.h>
47 
48 #include <net/if.h>
49 #include <net/if_var.h>
50 #include <net/if_dl.h>
51 #include <net/if_types.h>
52 #include <net/bridge.h>
53 #include <net/ethernet.h>
54 #include <netinet/in.h>
55 #include <netinet/in_var.h>
56 #include <netipx/ipx.h>
57 #include <netipx/ipx_if.h>
58 #ifdef NS
59 #include <netns/ns.h>
60 #include <netns/ns_if.h>
61 #endif
62 #ifdef ISO
63 #include <netiso/iso.h>
64 #include <netiso/iso_var.h>
65 #endif
66 #include <arpa/inet.h>
67 
68 #include <signal.h>
69 #include <stdio.h>
70 #include <stdlib.h>
71 #include <string.h>
72 #include <unistd.h>
73 
74 #include "netstat.h"
75 
76 #define	YES	1
77 #define	NO	0
78 
79 static void sidewaysintpr __P((u_int, u_long));
80 static void catchalarm __P((int));
81 
82 #ifdef INET6
83 char *netname6 __P((struct sockaddr_in6 *, struct in6_addr *));
84 static char ntop_buf[INET6_ADDRSTRLEN];		/* for inet_ntop() */
85 static int bdg_done;
86 #endif
87 
88 void
89 bdg_stats(u_long dummy, char *name) /* print bridge statistics */
90 {
91     int i;
92     size_t slen ;
93     struct bdg_stats s ;
94     int mib[4] ;
95 
96     slen = sizeof(s);
97 
98     mib[0] = CTL_NET ;
99     mib[1] = PF_LINK ;
100     mib[2] = IFT_ETHER ;
101     mib[3] = PF_BDG ;
102     if (sysctl(mib,4, &s,&slen,NULL,0)==-1)
103 	return ; /* no bridging */
104 #ifdef INET6
105     if (bdg_done != 0)
106 	return;
107     else
108 	bdg_done = 1;
109 #endif
110     printf("-- Bridging statistics (%s) --\n", name) ;
111     printf(
112 "Name          In      Out  Forward     Drop    Bcast    Mcast    Local  Unknown\n");
113     for (i = 0 ; i < 16 ; i++) {
114 	if (s.s[i].name[0])
115 	printf("%-6s %9ld%9ld%9ld%9ld%9ld%9ld%9ld%9ld\n",
116 	  s.s[i].name,
117 	  s.s[i].p_in[(int)BDG_IN],
118 	  s.s[i].p_in[(int)BDG_OUT],
119 	  s.s[i].p_in[(int)BDG_FORWARD],
120 	  s.s[i].p_in[(int)BDG_DROP],
121 	  s.s[i].p_in[(int)BDG_BCAST],
122 	  s.s[i].p_in[(int)BDG_MCAST],
123 	  s.s[i].p_in[(int)BDG_LOCAL],
124 	  s.s[i].p_in[(int)BDG_UNKNOWN] );
125     }
126 }
127 
128 
129 
130 
131 /*
132  * Display a formatted value, or a '-' in the same space.
133  */
134 void
135 show_stat(fmt, width, value, showvalue)
136 	char *fmt;
137 	int width;
138 	u_long value;
139 	short showvalue;
140 {
141 	char newfmt[32];
142 
143 	/* Construct the format string */
144 	if (showvalue) {
145 		sprintf(newfmt, "%%%d%s", width, fmt);
146 		printf(newfmt, value);
147 	} else {
148 		sprintf(newfmt, "%%%ds", width);
149 		printf(newfmt, "-");
150 	}
151 }
152 
153 
154 
155 /*
156  * Print a description of the network interfaces.
157  */
158 void
159 intpr(interval, ifnetaddr, pfunc)
160 	int interval;
161 	u_long ifnetaddr;
162 	void (*pfunc)(char *);
163 {
164 	struct ifnet ifnet;
165 	struct ifnethead ifnethead;
166 	union {
167 		struct ifaddr ifa;
168 		struct in_ifaddr in;
169 #ifdef INET6
170 		struct in6_ifaddr in6;
171 #endif
172 		struct ipx_ifaddr ipx;
173 #ifdef NS
174 		struct ns_ifaddr ns;
175 #endif
176 #ifdef ISO
177 		struct iso_ifaddr iso;
178 #endif
179 	} ifaddr;
180 	u_long ifaddraddr;
181 	u_long ifaddrfound;
182 	u_long ifnetfound;
183 	u_long opackets;
184 	u_long ipackets;
185 	u_long obytes;
186 	u_long ibytes;
187 	u_long oerrors;
188 	u_long ierrors;
189 	u_long collisions;
190 	short timer;
191 	int drops;
192 	struct sockaddr *sa = NULL;
193 	char name[32], tname[16];
194 	short network_layer;
195 	short link_layer;
196 
197 	if (ifnetaddr == 0) {
198 		printf("ifnet: symbol not defined\n");
199 		return;
200 	}
201 	if (interval) {
202 		sidewaysintpr((unsigned)interval, ifnetaddr);
203 		return;
204 	}
205 	if (kread(ifnetaddr, (char *)&ifnethead, sizeof ifnethead))
206 		return;
207 	ifnetaddr = (u_long)TAILQ_FIRST(&ifnethead);
208 	if (kread(ifnetaddr, (char *)&ifnet, sizeof ifnet))
209 		return;
210 
211 	if ((!sflag || iflag) && !pflag) {
212 		printf("%-5.5s %-5.5s %-13.13s %-15.15s %8.8s %5.5s",
213 		       "Name", "Mtu", "Network", "Address", "Ipkts", "Ierrs");
214 		if (bflag)
215 			printf(" %10.10s","Ibytes");
216 		printf(" %8.8s %5.5s", "Opkts", "Oerrs");
217 		if (bflag)
218 			printf(" %10.10s","Obytes");
219 		printf(" %5s", "Coll");
220 		if (tflag)
221 			printf(" %s", "Time");
222 		if (dflag)
223 			printf(" %s", "Drop");
224 		putchar('\n');
225 	}
226 	ifaddraddr = 0;
227 	while (ifnetaddr || ifaddraddr) {
228 		struct sockaddr_in *sin;
229 #ifdef INET6
230 		struct sockaddr_in6 *sin6;
231 #endif
232 		register char *cp;
233 		int n, m;
234 
235 		network_layer = 0;
236 		link_layer = 0;
237 
238 		if (ifaddraddr == 0) {
239 			ifnetfound = ifnetaddr;
240 			if (kread(ifnetaddr, (char *)&ifnet, sizeof ifnet) ||
241 			    kread((u_long)ifnet.if_name, tname, 16))
242 				return;
243 			tname[15] = '\0';
244 			ifnetaddr = (u_long)TAILQ_NEXT(&ifnet, if_link);
245 			snprintf(name, 32, "%s%d", tname, ifnet.if_unit);
246 			if (interface != 0 && (strcmp(name, interface) != 0))
247 				continue;
248 			cp = index(name, '\0');
249 
250 			if (pfunc) {
251 				(*pfunc)(name);
252 				continue;
253 			}
254 
255 			if ((ifnet.if_flags&IFF_UP) == 0)
256 				*cp++ = '*';
257 			*cp = '\0';
258 			ifaddraddr = (u_long)TAILQ_FIRST(&ifnet.if_addrhead);
259 		}
260 		printf("%-5.5s %-5lu ", name, ifnet.if_mtu);
261 		ifaddrfound = ifaddraddr;
262 
263 		/*
264 		 * Get the interface stats.  These may get
265 		 * overriden below on a per-interface basis.
266 		 */
267 		opackets = ifnet.if_opackets;
268 		ipackets = ifnet.if_ipackets;
269 		obytes = ifnet.if_obytes;
270 		ibytes = ifnet.if_ibytes;
271 		oerrors = ifnet.if_oerrors;
272 		ierrors = ifnet.if_ierrors;
273 		collisions = ifnet.if_collisions;
274 		timer = ifnet.if_timer;
275 		drops = ifnet.if_snd.ifq_drops;
276 
277 		if (ifaddraddr == 0) {
278 			printf("%-13.13s ", "none");
279 			printf("%-15.15s ", "none");
280 		} else {
281 			if (kread(ifaddraddr, (char *)&ifaddr, sizeof ifaddr)) {
282 				ifaddraddr = 0;
283 				continue;
284 			}
285 #define CP(x) ((char *)(x))
286 			cp = (CP(ifaddr.ifa.ifa_addr) - CP(ifaddraddr)) +
287 				CP(&ifaddr);
288 			sa = (struct sockaddr *)cp;
289 			switch (sa->sa_family) {
290 			case AF_UNSPEC:
291 				printf("%-13.13s ", "none");
292 				printf("%-15.15s ", "none");
293 				break;
294 			case AF_INET:
295 				sin = (struct sockaddr_in *)sa;
296 #ifdef notdef
297 				/* can't use inet_makeaddr because kernel
298 				 * keeps nets unshifted.
299 				 */
300 				in = inet_makeaddr(ifaddr.in.ia_subnet,
301 					INADDR_ANY);
302 				printf("%-13.13s ", netname(in.s_addr,
303 				    ifaddr.in.ia_subnetmask));
304 #else
305 				printf("%-13.13s ",
306 				    netname(htonl(ifaddr.in.ia_subnet),
307 				    ifaddr.in.ia_subnetmask));
308 #endif
309 				printf("%-15.15s ",
310 				    routename(sin->sin_addr.s_addr));
311 
312 				network_layer = 1;
313 				break;
314 #ifdef INET6
315 			case AF_INET6:
316 				sin6 = (struct sockaddr_in6 *)sa;
317 				printf("%-11.11s ",
318 				       netname6(&ifaddr.in6.ia_addr,
319 						&ifaddr.in6.ia_prefixmask.sin6_addr));
320 				printf("%-17.17s ",
321 				    (char *)inet_ntop(AF_INET6,
322 					&sin6->sin6_addr,
323 					ntop_buf, sizeof(ntop_buf)));
324 
325 				network_layer = 1;
326 				break;
327 #endif /*INET6*/
328 			case AF_IPX:
329 				{
330 				struct sockaddr_ipx *sipx =
331 					(struct sockaddr_ipx *)sa;
332 				u_long net;
333 				char netnum[10];
334 
335 				*(union ipx_net *) &net = sipx->sipx_addr.x_net;
336 				sprintf(netnum, "%lx", (u_long)ntohl(net));
337 				printf("ipx:%-8s  ", netnum);
338 /*				printf("ipx:%-8s ", netname(net, 0L)); */
339 				printf("%-15s ",
340 				    ipx_phost((struct sockaddr *)sipx));
341 				}
342 				break;
343 
344 			case AF_APPLETALK:
345 				printf("atalk:%-12.12s ",atalk_print(sa,0x10) );
346 				printf("%-9.9s  ",atalk_print(sa,0x0b) );
347 				break;
348 #ifdef NS
349 			case AF_NS:
350 				{
351 				struct sockaddr_ns *sns =
352 					(struct sockaddr_ns *)sa;
353 				u_long net;
354 				char netnum[10];
355 
356 				*(union ns_net *) &net = sns->sns_addr.x_net;
357 				sprintf(netnum, "%lxH", ntohl(net));
358 				upHex(netnum);
359 				printf("ns:%-8s ", netnum);
360 				printf("%-15s ",
361 				    ns_phost((struct sockaddr *)sns));
362 				}
363 				break;
364 #endif
365 			case AF_LINK:
366 				{
367 				struct sockaddr_dl *sdl =
368 					(struct sockaddr_dl *)sa;
369 				char linknum[10];
370 				cp = (char *)LLADDR(sdl);
371 				n = sdl->sdl_alen;
372 				sprintf(linknum, "<Link#%d>", sdl->sdl_index);
373 				m = printf("%-11.11s ", linknum);
374 				}
375 				goto hexprint;
376 			default:
377 				m = printf("(%d)", sa->sa_family);
378 				for (cp = sa->sa_len + (char *)sa;
379 					--cp > sa->sa_data && (*cp == 0);) {}
380 				n = cp - sa->sa_data + 1;
381 				cp = sa->sa_data;
382 			hexprint:
383 				while (--n >= 0)
384 					m += printf("%02x%c", *cp++ & 0xff,
385 						    n > 0 ? ':' : ' ');
386 				m = 30 - m;
387 				while (m-- > 0)
388 					putchar(' ');
389 
390 				link_layer = 1;
391 				break;
392 			}
393 
394 			/*
395 			 * Fixup the statistics for interfaces that
396 			 * update stats for their network addresses
397 			 */
398 			if (network_layer) {
399 				opackets = ifaddr.in.ia_ifa.if_opackets;
400 				ipackets = ifaddr.in.ia_ifa.if_ipackets;
401 				obytes = ifaddr.in.ia_ifa.if_obytes;
402 				ibytes = ifaddr.in.ia_ifa.if_ibytes;
403 			}
404 
405 			ifaddraddr = (u_long)TAILQ_NEXT(&ifaddr.ifa, ifa_link);
406 		}
407 
408 		show_stat("lu", 8, ipackets, link_layer|network_layer);
409 		printf(" ");
410 		show_stat("lu", 5, ierrors, link_layer);
411 		printf(" ");
412 		if (bflag) {
413 			show_stat("lu", 10, ibytes, link_layer|network_layer);
414 			printf(" ");
415 		}
416 		show_stat("lu", 8, opackets, link_layer|network_layer);
417 		printf(" ");
418 		show_stat("lu", 5, oerrors, link_layer);
419 		printf(" ");
420 		if (bflag) {
421 			show_stat("lu", 10, obytes, link_layer|network_layer);
422 			printf(" ");
423 		}
424 		show_stat("lu", 5, collisions, link_layer);
425 		if (tflag) {
426 			printf(" ");
427 			show_stat("d", 3, timer, link_layer);
428 		}
429 		if (dflag) {
430 			printf(" ");
431 			show_stat("d", 3, drops, link_layer);
432 		}
433 		putchar('\n');
434 		if (aflag && ifaddrfound) {
435 			/*
436 			 * Print family's multicast addresses
437 			 */
438 			struct ifmultiaddr *multiaddr;
439 			struct ifmultiaddr ifma;
440 			union {
441 				struct sockaddr sa;
442 				struct sockaddr_in in;
443 #ifdef INET6
444 				struct sockaddr_in6 in6;
445 #endif /* INET6 */
446 				struct sockaddr_dl dl;
447 			} msa;
448 			const char *fmt;
449 
450 			TAILQ_FOREACH(multiaddr, &ifnet.if_multiaddrs, ifma_link) {
451 				if (kread((u_long)multiaddr, (char *)&ifma,
452 					  sizeof ifma))
453 					break;
454 				multiaddr = &ifma;
455 				if (kread((u_long)ifma.ifma_addr, (char *)&msa,
456 					  sizeof msa))
457 					break;
458 				if (msa.sa.sa_family != sa->sa_family)
459 					continue;
460 
461 				fmt = 0;
462 				switch (msa.sa.sa_family) {
463 				case AF_INET:
464 					fmt = routename(msa.in.sin_addr.s_addr);
465 					break;
466 #ifdef INET6
467 				case AF_INET6:
468 					printf("%23s %-19.19s(refs: %d)\n", "",
469 					       inet_ntop(AF_INET6,
470 							 &msa.in6.sin6_addr,
471 							 ntop_buf,
472 							 sizeof(ntop_buf)),
473 					       ifma.ifma_refcount);
474 					break;
475 #endif /* INET6 */
476 				case AF_LINK:
477 					switch (msa.dl.sdl_type) {
478 					case IFT_ETHER:
479 					case IFT_FDDI:
480 						fmt = ether_ntoa(
481 							(struct ether_addr *)
482 							LLADDR(&msa.dl));
483 						break;
484 					}
485 					break;
486 				}
487 				if (fmt)
488 					printf("%23s %s\n", "", fmt);
489 			}
490 		}
491 	}
492 }
493 
494 struct	iftot {
495 	SLIST_ENTRY(iftot) chain;
496 	char	ift_name[16];		/* interface name */
497 	u_long	ift_ip;			/* input packets */
498 	u_long	ift_ie;			/* input errors */
499 	u_long	ift_op;			/* output packets */
500 	u_long	ift_oe;			/* output errors */
501 	u_long	ift_co;			/* collisions */
502 	u_int	ift_dr;			/* drops */
503 	u_long	ift_ib;			/* input bytes */
504 	u_long	ift_ob;			/* output bytes */
505 };
506 
507 u_char	signalled;			/* set if alarm goes off "early" */
508 
509 /*
510  * Print a running summary of interface statistics.
511  * Repeat display every interval seconds, showing statistics
512  * collected over that interval.  Assumes that interval is non-zero.
513  * First line printed at top of screen is always cumulative.
514  * XXX - should be rewritten to use ifmib(4).
515  */
516 static void
517 sidewaysintpr(interval, off)
518 	unsigned interval;
519 	u_long off;
520 {
521 	struct ifnet ifnet;
522 	u_long firstifnet;
523 	struct ifnethead ifnethead;
524 	struct iftot *iftot, *ip, *ipn, *total, *sum, *interesting;
525 	register int line;
526 	int oldmask, first;
527 	u_long interesting_off;
528 
529 	if (kread(off, (char *)&ifnethead, sizeof ifnethead))
530 		return;
531 	firstifnet = (u_long)TAILQ_FIRST(&ifnethead);
532 
533 	if ((iftot = malloc(sizeof(struct iftot))) == NULL) {
534 		printf("malloc failed\n");
535 		exit(1);
536 	}
537 	memset(iftot, 0, sizeof(struct iftot));
538 
539 	interesting = NULL;
540 	interesting_off = 0;
541 	for (off = firstifnet, ip = iftot; off;) {
542 		char name[16], tname[16];
543 
544 		if (kread(off, (char *)&ifnet, sizeof ifnet))
545 			break;
546 		if (kread((u_long)ifnet.if_name, tname, 16))
547 			break;
548 		tname[15] = '\0';
549 		snprintf(name, 16, "%s%d", tname, ifnet.if_unit);
550 		if (interface && strcmp(name, interface) == 0) {
551 			interesting = ip;
552 			interesting_off = off;
553 		}
554 		snprintf(ip->ift_name, 16, "(%s)", name);;
555 		if ((ipn = malloc(sizeof(struct iftot))) == NULL) {
556 			printf("malloc failed\n");
557 			exit(1);
558 		}
559 		memset(ipn, 0, sizeof(struct iftot));
560 		SLIST_NEXT(ip, chain) = ipn;
561 		ip = ipn;
562 		off = (u_long)TAILQ_NEXT(&ifnet, if_link);
563 	}
564 	if ((total = malloc(sizeof(struct iftot))) == NULL) {
565 		printf("malloc failed\n");
566 		exit(1);
567 	}
568 	memset(total, 0, sizeof(struct iftot));
569 	if ((sum = malloc(sizeof(struct iftot))) == NULL) {
570 		printf("malloc failed\n");
571 		exit(1);
572 	}
573 	memset(sum, 0, sizeof(struct iftot));
574 
575 
576 	(void)signal(SIGALRM, catchalarm);
577 	signalled = NO;
578 	(void)alarm(interval);
579 	first = 1;
580 banner:
581 	printf("%17s %14s %16s", "input",
582 	    interesting ? interesting->ift_name : "(Total)", "output");
583 	putchar('\n');
584 	printf("%10s %5s %10s %10s %5s %10s %5s",
585 	    "packets", "errs", "bytes", "packets", "errs", "bytes", "colls");
586 	if (dflag)
587 		printf(" %5.5s", "drops");
588 	putchar('\n');
589 	fflush(stdout);
590 	line = 0;
591 loop:
592 	if (interesting != NULL) {
593 		ip = interesting;
594 		if (kread(interesting_off, (char *)&ifnet, sizeof ifnet)) {
595 			printf("???\n");
596 			exit(1);
597 		};
598 		if (!first) {
599 			printf("%10lu %5lu %10lu %10lu %5lu %10lu %5lu",
600 				ifnet.if_ipackets - ip->ift_ip,
601 				ifnet.if_ierrors - ip->ift_ie,
602 				ifnet.if_ibytes - ip->ift_ib,
603 				ifnet.if_opackets - ip->ift_op,
604 				ifnet.if_oerrors - ip->ift_oe,
605 				ifnet.if_obytes - ip->ift_ob,
606 				ifnet.if_collisions - ip->ift_co);
607 			if (dflag)
608 				printf(" %5u", ifnet.if_snd.ifq_drops - ip->ift_dr);
609 		}
610 		ip->ift_ip = ifnet.if_ipackets;
611 		ip->ift_ie = ifnet.if_ierrors;
612 		ip->ift_ib = ifnet.if_ibytes;
613 		ip->ift_op = ifnet.if_opackets;
614 		ip->ift_oe = ifnet.if_oerrors;
615 		ip->ift_ob = ifnet.if_obytes;
616 		ip->ift_co = ifnet.if_collisions;
617 		ip->ift_dr = ifnet.if_snd.ifq_drops;
618 	} else {
619 		sum->ift_ip = 0;
620 		sum->ift_ie = 0;
621 		sum->ift_ib = 0;
622 		sum->ift_op = 0;
623 		sum->ift_oe = 0;
624 		sum->ift_ob = 0;
625 		sum->ift_co = 0;
626 		sum->ift_dr = 0;
627 		for (off = firstifnet, ip = iftot;
628 		     off && SLIST_NEXT(ip, chain) != NULL;
629 		     ip = SLIST_NEXT(ip, chain)) {
630 			if (kread(off, (char *)&ifnet, sizeof ifnet)) {
631 				off = 0;
632 				continue;
633 			}
634 			sum->ift_ip += ifnet.if_ipackets;
635 			sum->ift_ie += ifnet.if_ierrors;
636 			sum->ift_ib += ifnet.if_ibytes;
637 			sum->ift_op += ifnet.if_opackets;
638 			sum->ift_oe += ifnet.if_oerrors;
639 			sum->ift_ob += ifnet.if_obytes;
640 			sum->ift_co += ifnet.if_collisions;
641 			sum->ift_dr += ifnet.if_snd.ifq_drops;
642 			off = (u_long)TAILQ_NEXT(&ifnet, if_link);
643 		}
644 		if (!first) {
645 			printf("%10lu %5lu %10lu %10lu %5lu %10lu %5lu",
646 				sum->ift_ip - total->ift_ip,
647 				sum->ift_ie - total->ift_ie,
648 				sum->ift_ib - total->ift_ib,
649 				sum->ift_op - total->ift_op,
650 				sum->ift_oe - total->ift_oe,
651 				sum->ift_ob - total->ift_ob,
652 				sum->ift_co - total->ift_co);
653 			if (dflag)
654 				printf(" %5u", sum->ift_dr - total->ift_dr);
655 		}
656 		*total = *sum;
657 	}
658 	if (!first)
659 		putchar('\n');
660 	fflush(stdout);
661 	oldmask = sigblock(sigmask(SIGALRM));
662 	if (! signalled) {
663 		sigpause(0);
664 	}
665 	sigsetmask(oldmask);
666 	signalled = NO;
667 	(void)alarm(interval);
668 	line++;
669 	first = 0;
670 	if (line == 21)
671 		goto banner;
672 	else
673 		goto loop;
674 	/*NOTREACHED*/
675 }
676 
677 /*
678  * Called if an interval expires before sidewaysintpr has completed a loop.
679  * Sets a flag to not wait for the alarm.
680  */
681 static void
682 catchalarm(signo)
683 	int signo;
684 {
685 	signalled = YES;
686 }
687