xref: /dragonfly/usr.bin/netstat/if.c (revision 6bd457ed)
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  * @(#)if.c	8.3 (Berkeley) 4/28/95
34  * $FreeBSD: src/usr.bin/netstat/if.c,v 1.32.2.9 2001/09/17 14:35:46 ru Exp $
35  * $DragonFly: src/usr.bin/netstat/if.c,v 1.8 2005/08/04 17:31:23 drhodus Exp $
36  */
37 
38 #include <sys/param.h>
39 #include <sys/protosw.h>
40 #include <sys/socket.h>
41 #include <sys/sysctl.h>
42 #include <sys/time.h>
43 
44 #include <net/if.h>
45 #include <net/if_var.h>
46 #include <net/if_dl.h>
47 #include <net/if_types.h>
48 #include <net/bridge/bridge.h>
49 #include <net/ethernet.h>
50 #include <netinet/in.h>
51 #include <netinet/in_var.h>
52 #include <netproto/ipx/ipx.h>
53 #include <netproto/ipx/ipx_if.h>
54 #ifdef NS
55 #include <netproto/ns/ns.h>
56 #include <netproto/ns/ns_if.h>
57 #endif
58 #ifdef ISO
59 #include <netiso/iso.h>
60 #include <netiso/iso_var.h>
61 #endif
62 #include <arpa/inet.h>
63 
64 #include <signal.h>
65 #include <stdio.h>
66 #include <stdlib.h>
67 #include <string.h>
68 #include <unistd.h>
69 
70 #include "netstat.h"
71 
72 #define	YES	1
73 #define	NO	0
74 
75 static void sidewaysintpr (u_int, u_long);
76 static void catchalarm (int);
77 
78 #ifdef INET6
79 char *netname6 (struct sockaddr_in6 *, struct in6_addr *);
80 static char ntop_buf[INET6_ADDRSTRLEN];		/* for inet_ntop() */
81 static int bdg_done;
82 #endif
83 
84 /* print bridge statistics */
85 void
86 bdg_stats(u_long dummy __unused, char *name, int af __unused)
87 {
88     int i;
89     size_t slen ;
90     struct bdg_stats s ;
91     int mib[4] ;
92 
93     slen = sizeof(s);
94 
95     mib[0] = CTL_NET ;
96     mib[1] = PF_LINK ;
97     mib[2] = IFT_ETHER ;
98     mib[3] = PF_BDG ;
99     if (sysctl(mib,4, &s,&slen,NULL,0)==-1)
100 	return ; /* no bridging */
101 #ifdef INET6
102     if (bdg_done != 0)
103 	return;
104     else
105 	bdg_done = 1;
106 #endif
107     printf("-- Bridging statistics (%s) --\n", name) ;
108     printf(
109 "Name          In      Out  Forward     Drop    Bcast    Mcast    Local  Unknown\n");
110     for (i = 0 ; i < 16 ; i++) {
111 	if (s.s[i].name[0])
112 	printf("%-6s %9ld%9ld%9ld%9ld%9ld%9ld%9ld%9ld\n",
113 	  s.s[i].name,
114 	  s.s[i].p_in[(int)BDG_IN],
115 	  s.s[i].p_in[(int)BDG_OUT],
116 	  s.s[i].p_in[(int)BDG_FORWARD],
117 	  s.s[i].p_in[(int)BDG_DROP],
118 	  s.s[i].p_in[(int)BDG_BCAST],
119 	  s.s[i].p_in[(int)BDG_MCAST],
120 	  s.s[i].p_in[(int)BDG_LOCAL],
121 	  s.s[i].p_in[(int)BDG_UNKNOWN] );
122     }
123 }
124 
125 
126 
127 
128 /*
129  * Display a formatted value, or a '-' in the same space.
130  */
131 static void
132 show_stat(const char *fmt, int width, u_long value, short showvalue)
133 {
134 	char newfmt[32];
135 
136 	/* Construct the format string */
137 	if (showvalue) {
138 		sprintf(newfmt, "%%%d%s", width, fmt);
139 		printf(newfmt, value);
140 	} else {
141 		sprintf(newfmt, "%%%ds", width);
142 		printf(newfmt, "-");
143 	}
144 }
145 
146 
147 
148 /*
149  * Print a description of the network interfaces.
150  */
151 void
152 intpr(int interval, u_long ifnetaddr, void (*pfunc)(char *))
153 {
154 	struct ifnet ifnet;
155 	struct ifnethead ifnethead;
156 	union {
157 		struct ifaddr ifa;
158 		struct in_ifaddr in;
159 #ifdef INET6
160 		struct in6_ifaddr in6;
161 #endif
162 		struct ipx_ifaddr ipx;
163 #ifdef NS
164 		struct ns_ifaddr ns;
165 #endif
166 #ifdef ISO
167 		struct iso_ifaddr iso;
168 #endif
169 	} ifaddr;
170 	u_long ifaddraddr;
171 	u_long ifaddrfound;
172 	u_long ifnetfound;
173 	u_long opackets;
174 	u_long ipackets;
175 	u_long obytes;
176 	u_long ibytes;
177 	u_long oerrors;
178 	u_long ierrors;
179 	u_long collisions;
180 	short timer;
181 	int drops;
182 	struct sockaddr *sa = NULL;
183 	char name[IFNAMSIZ];
184 	short network_layer;
185 	short link_layer;
186 
187 	if (ifnetaddr == 0) {
188 		printf("ifnet: symbol not defined\n");
189 		return;
190 	}
191 	if (interval) {
192 		sidewaysintpr((unsigned)interval, ifnetaddr);
193 		return;
194 	}
195 	if (kread(ifnetaddr, (char *)&ifnethead, sizeof ifnethead))
196 		return;
197 	ifnetaddr = (u_long)TAILQ_FIRST(&ifnethead);
198 	if (kread(ifnetaddr, (char *)&ifnet, sizeof ifnet))
199 		return;
200 
201 	if (!pfunc) {
202 		printf("%-7.7s %-5.5s %-13.13s %-15.15s %8.8s %5.5s",
203 		       "Name", "Mtu", "Network", "Address", "Ipkts", "Ierrs");
204 		if (bflag)
205 			printf(" %10.10s","Ibytes");
206 		printf(" %8.8s %5.5s", "Opkts", "Oerrs");
207 		if (bflag)
208 			printf(" %10.10s","Obytes");
209 		printf(" %5s", "Coll");
210 		if (tflag)
211 			printf(" %s", "Time");
212 		if (dflag)
213 			printf(" %s", "Drop");
214 		putchar('\n');
215 	}
216 	ifaddraddr = 0;
217 	while (ifnetaddr || ifaddraddr) {
218 		struct sockaddr_in *sin;
219 #ifdef INET6
220 		struct sockaddr_in6 *sin6;
221 #endif
222 		char *cp;
223 		int n, m;
224 
225 		network_layer = 0;
226 		link_layer = 0;
227 
228 		if (ifaddraddr == 0) {
229 			ifnetfound = ifnetaddr;
230 			if (kread(ifnetaddr, (char *)&ifnet, sizeof ifnet))
231 				return;
232 			strlcpy(name, ifnet.if_xname, sizeof(name));
233 			ifnetaddr = (u_long)TAILQ_NEXT(&ifnet, if_link);
234 			if (interface != 0 && (strcmp(name, interface) != 0))
235 				continue;
236 			cp = strchr(name, '\0');
237 
238 			if (pfunc) {
239 				(*pfunc)(name);
240 				continue;
241 			}
242 
243 			if ((ifnet.if_flags&IFF_UP) == 0)
244 				*cp++ = '*';
245 			*cp = '\0';
246 			ifaddraddr = (u_long)TAILQ_FIRST(&ifnet.if_addrhead);
247 		}
248 		ifaddrfound = ifaddraddr;
249 
250 		/*
251 		 * Get the interface stats.  These may get
252 		 * overriden below on a per-interface basis.
253 		 */
254 		opackets = ifnet.if_opackets;
255 		ipackets = ifnet.if_ipackets;
256 		obytes = ifnet.if_obytes;
257 		ibytes = ifnet.if_ibytes;
258 		oerrors = ifnet.if_oerrors;
259 		ierrors = ifnet.if_ierrors;
260 		collisions = ifnet.if_collisions;
261 		timer = ifnet.if_timer;
262 		drops = ifnet.if_snd.ifq_drops;
263 
264 		if (ifaddraddr == 0) {
265 			printf("%-7.7s %-5lu ", name, ifnet.if_mtu);
266 			printf("%-13.13s ", "none");
267 			printf("%-15.15s ", "none");
268 		} else {
269 			if (kread(ifaddraddr, (char *)&ifaddr, sizeof ifaddr)) {
270 				ifaddraddr = 0;
271 				continue;
272 			}
273 #define CP(x) ((char *)(x))
274 			cp = (CP(ifaddr.ifa.ifa_addr) - CP(ifaddraddr)) +
275 				CP(&ifaddr);
276 			sa = (struct sockaddr *)cp;
277 			if (af != AF_UNSPEC && sa->sa_family != af) {
278 				ifaddraddr =
279 				    (u_long)TAILQ_NEXT(&ifaddr.ifa, ifa_link);
280 				continue;
281 			}
282 			printf("%-7.7s %-5lu ", name, ifnet.if_mtu);
283 			switch (sa->sa_family) {
284 			case AF_UNSPEC:
285 				printf("%-13.13s ", "none");
286 				printf("%-15.15s ", "none");
287 				break;
288 			case AF_INET:
289 				sin = (struct sockaddr_in *)sa;
290 #ifdef notdef
291 				/* can't use inet_makeaddr because kernel
292 				 * keeps nets unshifted.
293 				 */
294 				in = inet_makeaddr(ifaddr.in.ia_subnet,
295 					INADDR_ANY);
296 				printf("%-13.13s ", netname(in.s_addr,
297 				    ifaddr.in.ia_subnetmask));
298 #else
299 				printf("%-13.13s ",
300 				    netname(htonl(ifaddr.in.ia_subnet),
301 				    ifaddr.in.ia_subnetmask));
302 #endif
303 				printf("%-15.15s ",
304 				    routename(sin->sin_addr.s_addr));
305 
306 				network_layer = 1;
307 				break;
308 #ifdef INET6
309 			case AF_INET6:
310 				sin6 = (struct sockaddr_in6 *)sa;
311 				printf("%-11.11s ",
312 				       netname6(&ifaddr.in6.ia_addr,
313 						&ifaddr.in6.ia_prefixmask.sin6_addr));
314 				printf("%-17.17s ",
315 				    (char *)inet_ntop(AF_INET6,
316 					&sin6->sin6_addr,
317 					ntop_buf, sizeof(ntop_buf)));
318 
319 				network_layer = 1;
320 				break;
321 #endif /*INET6*/
322 			case AF_IPX:
323 				{
324 				struct sockaddr_ipx *sipx =
325 					(struct sockaddr_ipx *)sa;
326 				u_long net;
327 				char netnum[10];
328 
329 				*(union ipx_net *) &net = sipx->sipx_addr.x_net;
330 				sprintf(netnum, "%lx", (u_long)ntohl(net));
331 				printf("ipx:%-8s  ", netnum);
332 /*				printf("ipx:%-8s ", netname(net, 0L)); */
333 				printf("%-15s ",
334 				    ipx_phost((struct sockaddr *)sipx));
335 				}
336 				break;
337 
338 			case AF_APPLETALK:
339 				printf("atalk:%-12.12s ",atalk_print(sa,0x10) );
340 				printf("%-9.9s  ",atalk_print(sa,0x0b) );
341 				break;
342 #ifdef NS
343 			case AF_NS:
344 				{
345 				struct sockaddr_ns *sns =
346 					(struct sockaddr_ns *)sa;
347 				u_long net;
348 				char netnum[10];
349 
350 				*(union ns_net *) &net = sns->sns_addr.x_net;
351 				sprintf(netnum, "%lxH", ntohl(net));
352 				upHex(netnum);
353 				printf("ns:%-8s ", netnum);
354 				printf("%-15s ",
355 				    ns_phost((struct sockaddr *)sns));
356 				}
357 				break;
358 #endif
359 			case AF_LINK:
360 				{
361 				struct sockaddr_dl *sdl =
362 					(struct sockaddr_dl *)sa;
363 				char linknum[10];
364 				cp = (char *)LLADDR(sdl);
365 				n = sdl->sdl_alen;
366 				sprintf(linknum, "<Link#%d>", sdl->sdl_index);
367 				m = printf("%-11.11s ", linknum);
368 				}
369 				goto hexprint;
370 			default:
371 				m = printf("(%d)", sa->sa_family);
372 				for (cp = sa->sa_len + (char *)sa;
373 					--cp > sa->sa_data && (*cp == 0);) {}
374 				n = cp - sa->sa_data + 1;
375 				cp = sa->sa_data;
376 			hexprint:
377 				while (--n >= 0)
378 					m += printf("%02x%c", *cp++ & 0xff,
379 						    n > 0 ? ':' : ' ');
380 				m = 30 - m;
381 				while (m-- > 0)
382 					putchar(' ');
383 
384 				link_layer = 1;
385 				break;
386 			}
387 
388 			/*
389 			 * Fixup the statistics for interfaces that
390 			 * update stats for their network addresses
391 			 */
392 			if (network_layer) {
393 				opackets = ifaddr.in.ia_ifa.if_opackets;
394 				ipackets = ifaddr.in.ia_ifa.if_ipackets;
395 				obytes = ifaddr.in.ia_ifa.if_obytes;
396 				ibytes = ifaddr.in.ia_ifa.if_ibytes;
397 			}
398 
399 			ifaddraddr = (u_long)TAILQ_NEXT(&ifaddr.ifa, ifa_link);
400 		}
401 
402 		show_stat("lu", 8, ipackets, link_layer|network_layer);
403 		printf(" ");
404 		show_stat("lu", 5, ierrors, link_layer);
405 		printf(" ");
406 		if (bflag) {
407 			show_stat("lu", 10, ibytes, link_layer|network_layer);
408 			printf(" ");
409 		}
410 		show_stat("lu", 8, opackets, link_layer|network_layer);
411 		printf(" ");
412 		show_stat("lu", 5, oerrors, link_layer);
413 		printf(" ");
414 		if (bflag) {
415 			show_stat("lu", 10, obytes, link_layer|network_layer);
416 			printf(" ");
417 		}
418 		show_stat("lu", 5, collisions, link_layer);
419 		if (tflag) {
420 			printf(" ");
421 			show_stat("d", 3, timer, link_layer);
422 		}
423 		if (dflag) {
424 			printf(" ");
425 			show_stat("d", 3, drops, link_layer);
426 		}
427 		putchar('\n');
428 		if (aflag && ifaddrfound) {
429 			/*
430 			 * Print family's multicast addresses
431 			 */
432 			u_long multiaddr;
433 			struct ifmultiaddr ifma;
434 			union {
435 				struct sockaddr sa;
436 				struct sockaddr_in in;
437 #ifdef INET6
438 				struct sockaddr_in6 in6;
439 #endif /* INET6 */
440 				struct sockaddr_dl dl;
441 			} msa;
442 			const char *fmt;
443 
444 			for(multiaddr = (u_long)ifnet.if_multiaddrs.lh_first;
445 			    multiaddr;
446 			    multiaddr = (u_long)ifma.ifma_link.le_next) {
447 				if (kread(multiaddr, (char *)&ifma,
448 					  sizeof ifma))
449 					break;
450 				if (kread((u_long)ifma.ifma_addr, (char *)&msa,
451 					  sizeof msa))
452 					break;
453 				if (msa.sa.sa_family != sa->sa_family)
454 					continue;
455 
456 				fmt = 0;
457 				switch (msa.sa.sa_family) {
458 				case AF_INET:
459 					fmt = routename(msa.in.sin_addr.s_addr);
460 					break;
461 #ifdef INET6
462 				case AF_INET6:
463 					printf("%23s %-19.19s(refs: %d)\n", "",
464 					       inet_ntop(AF_INET6,
465 							 &msa.in6.sin6_addr,
466 							 ntop_buf,
467 							 sizeof(ntop_buf)),
468 					       ifma.ifma_refcount);
469 					break;
470 #endif /* INET6 */
471 				case AF_LINK:
472 					switch (msa.dl.sdl_type) {
473 					case IFT_ETHER:
474 					case IFT_FDDI:
475 						fmt = ether_ntoa(
476 							(struct ether_addr *)
477 							LLADDR(&msa.dl));
478 						break;
479 					}
480 					break;
481 				}
482 				if (fmt)
483 					printf("%23s %s\n", "", fmt);
484 			}
485 		}
486 	}
487 }
488 
489 struct	iftot {
490 	SLIST_ENTRY(iftot) chain;
491 	char	ift_name[IFNAMSIZ];	/* interface name */
492 	u_long	ift_ip;			/* input packets */
493 	u_long	ift_ie;			/* input errors */
494 	u_long	ift_op;			/* output packets */
495 	u_long	ift_oe;			/* output errors */
496 	u_long	ift_co;			/* collisions */
497 	u_int	ift_dr;			/* drops */
498 	u_long	ift_ib;			/* input bytes */
499 	u_long	ift_ob;			/* output bytes */
500 };
501 
502 u_char	signalled;			/* set if alarm goes off "early" */
503 
504 /*
505  * Print a running summary of interface statistics.
506  * Repeat display every interval seconds, showing statistics
507  * collected over that interval.  Assumes that interval is non-zero.
508  * First line printed at top of screen is always cumulative.
509  * XXX - should be rewritten to use ifmib(4).
510  */
511 static void
512 sidewaysintpr(unsigned interval, u_long off)
513 {
514 	struct ifnet ifnet;
515 	u_long firstifnet;
516 	struct ifnethead ifnethead;
517 	struct iftot *iftot, *ip, *ipn, *total, *sum, *interesting;
518 	int line;
519 	int oldmask, first;
520 	u_long interesting_off;
521 
522 	if (kread(off, (char *)&ifnethead, sizeof ifnethead))
523 		return;
524 	firstifnet = (u_long)TAILQ_FIRST(&ifnethead);
525 
526 	if ((iftot = malloc(sizeof(struct iftot))) == NULL) {
527 		printf("malloc failed\n");
528 		exit(1);
529 	}
530 	memset(iftot, 0, sizeof(struct iftot));
531 
532 	interesting = NULL;
533 	interesting_off = 0;
534 	for (off = firstifnet, ip = iftot; off;) {
535 		char name[IFNAMSIZ];
536 
537 		if (kread(off, (char *)&ifnet, sizeof ifnet))
538 			break;
539 		strlcpy(name, ifnet.if_xname, sizeof(name));
540 		if (interface && strcmp(name, interface) == 0) {
541 			interesting = ip;
542 			interesting_off = off;
543 		}
544 		snprintf(ip->ift_name, 16, "(%s)", name);;
545 		if ((ipn = malloc(sizeof(struct iftot))) == NULL) {
546 			printf("malloc failed\n");
547 			exit(1);
548 		}
549 		memset(ipn, 0, sizeof(struct iftot));
550 		SLIST_NEXT(ip, chain) = ipn;
551 		ip = ipn;
552 		off = (u_long)TAILQ_NEXT(&ifnet, if_link);
553 	}
554 	if ((total = malloc(sizeof(struct iftot))) == NULL) {
555 		printf("malloc failed\n");
556 		exit(1);
557 	}
558 	memset(total, 0, sizeof(struct iftot));
559 	if ((sum = malloc(sizeof(struct iftot))) == NULL) {
560 		printf("malloc failed\n");
561 		exit(1);
562 	}
563 	memset(sum, 0, sizeof(struct iftot));
564 
565 
566 	(void)signal(SIGALRM, catchalarm);
567 	signalled = NO;
568 	(void)alarm(interval);
569 	first = 1;
570 banner:
571 	printf("%17s %14s %16s", "input",
572 	    interesting ? interesting->ift_name : "(Total)", "output");
573 	putchar('\n');
574 	printf("%10s %5s %10s %10s %5s %10s %5s",
575 	    "packets", "errs", "bytes", "packets", "errs", "bytes", "colls");
576 	if (dflag)
577 		printf(" %5.5s", "drops");
578 	putchar('\n');
579 	fflush(stdout);
580 	line = 0;
581 loop:
582 	if (interesting != NULL) {
583 		ip = interesting;
584 		if (kread(interesting_off, (char *)&ifnet, sizeof ifnet)) {
585 			printf("???\n");
586 			exit(1);
587 		};
588 		if (!first) {
589 			printf("%10lu %5lu %10lu %10lu %5lu %10lu %5lu",
590 				ifnet.if_ipackets - ip->ift_ip,
591 				ifnet.if_ierrors - ip->ift_ie,
592 				ifnet.if_ibytes - ip->ift_ib,
593 				ifnet.if_opackets - ip->ift_op,
594 				ifnet.if_oerrors - ip->ift_oe,
595 				ifnet.if_obytes - ip->ift_ob,
596 				ifnet.if_collisions - ip->ift_co);
597 			if (dflag)
598 				printf(" %5u", ifnet.if_snd.ifq_drops - ip->ift_dr);
599 		}
600 		ip->ift_ip = ifnet.if_ipackets;
601 		ip->ift_ie = ifnet.if_ierrors;
602 		ip->ift_ib = ifnet.if_ibytes;
603 		ip->ift_op = ifnet.if_opackets;
604 		ip->ift_oe = ifnet.if_oerrors;
605 		ip->ift_ob = ifnet.if_obytes;
606 		ip->ift_co = ifnet.if_collisions;
607 		ip->ift_dr = ifnet.if_snd.ifq_drops;
608 	} else {
609 		sum->ift_ip = 0;
610 		sum->ift_ie = 0;
611 		sum->ift_ib = 0;
612 		sum->ift_op = 0;
613 		sum->ift_oe = 0;
614 		sum->ift_ob = 0;
615 		sum->ift_co = 0;
616 		sum->ift_dr = 0;
617 		for (off = firstifnet, ip = iftot;
618 		     off && SLIST_NEXT(ip, chain) != NULL;
619 		     ip = SLIST_NEXT(ip, chain)) {
620 			if (kread(off, (char *)&ifnet, sizeof ifnet)) {
621 				off = 0;
622 				continue;
623 			}
624 			sum->ift_ip += ifnet.if_ipackets;
625 			sum->ift_ie += ifnet.if_ierrors;
626 			sum->ift_ib += ifnet.if_ibytes;
627 			sum->ift_op += ifnet.if_opackets;
628 			sum->ift_oe += ifnet.if_oerrors;
629 			sum->ift_ob += ifnet.if_obytes;
630 			sum->ift_co += ifnet.if_collisions;
631 			sum->ift_dr += ifnet.if_snd.ifq_drops;
632 			off = (u_long)TAILQ_NEXT(&ifnet, if_link);
633 		}
634 		if (!first) {
635 			printf("%10lu %5lu %10lu %10lu %5lu %10lu %5lu",
636 				sum->ift_ip - total->ift_ip,
637 				sum->ift_ie - total->ift_ie,
638 				sum->ift_ib - total->ift_ib,
639 				sum->ift_op - total->ift_op,
640 				sum->ift_oe - total->ift_oe,
641 				sum->ift_ob - total->ift_ob,
642 				sum->ift_co - total->ift_co);
643 			if (dflag)
644 				printf(" %5u", sum->ift_dr - total->ift_dr);
645 		}
646 		*total = *sum;
647 	}
648 	if (!first)
649 		putchar('\n');
650 	fflush(stdout);
651 	oldmask = sigblock(sigmask(SIGALRM));
652 	if (! signalled) {
653 		sigpause(0);
654 	}
655 	sigsetmask(oldmask);
656 	signalled = NO;
657 	(void)alarm(interval);
658 	line++;
659 	first = 0;
660 	if (line == 21)
661 		goto banner;
662 	else
663 		goto loop;
664 	/*NOTREACHED*/
665 }
666 
667 /*
668  * Called if an interval expires before sidewaysintpr has completed a loop.
669  * Sets a flag to not wait for the alarm.
670  */
671 static void
672 catchalarm(int signo __unused)
673 {
674 	signalled = YES;
675 }
676