text: /*
   * Copyright (c) 1983, 1988, 1993
   *	Regents of the University of California.  All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. All advertising materials mentioning features or use of this software
   *    must display the following acknowledgement:
   *	This product includes software developed by the University of
   *	California, Berkeley and its contributors.
   * 4. Neither the name of the University nor the names of its contributors
   *    may be used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   *
   * @(#) Copyright (c) 1983, 1988, 1993 Regents of the University of California.  All rights reserved.
   * @(#)main.c	8.4 (Berkeley) 3/1/94
   * $FreeBSD: src/usr.bin/netstat/main.c,v 1.34.2.12 2001/09/17 15:17:46 ru Exp $
   */
  
  #include <sys/param.h>
  #include <sys/file.h>
  #include <sys/protosw.h>
  #include <sys/socket.h>
  
  #include <netinet/in.h>
  
  #include <netgraph/socket/ng_socket.h>
  
  #include <ctype.h>
  #include <err.h>
  #include <errno.h>
  #include <kvm.h>
  #include <limits.h>
  #include <netdb.h>
  #include <nlist.h>
  #include <paths.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <unistd.h>
  #include "netstat.h"
  
  static struct nlist nl[] = {
  #define	N_IFNET		0
  	{ .n_name = "_ifnet" },
  #define	N_IMP		1
  	{ .n_name = "_imp_softc" },
  #define	N_RTSTAT	2
  	{ .n_name = "_rtstat" },
  #define	N_UNIXSW	3
  	{ .n_name = "_localsw" },
  #define N_IDP		4
  	{ .n_name = "_nspcb"},
  #define N_IDPSTAT	5
  	{ .n_name = "_idpstat"},
  #define N_SPPSTAT	6
  	{ .n_name = "_spp_istat"},
  #define N_NSERR		7
  	{ .n_name = "_ns_errstat"},
  #define	N_CLNPSTAT	8
  	{ .n_name = "_clnp_stat"},
  #define	IN_NOTUSED	9
  	{ .n_name = "_tp_inpcb" },
  #define	ISO_TP		10
  	{ .n_name = "_tp_refinfo" },
  #define	N_TPSTAT	11
  	{ .n_name = "_tp_stat" },
  #define	N_ESISSTAT	12
  	{ .n_name = "_esis_stat"},
  #define N_NIMP		13
  	{ .n_name = "_nimp"},
  #define N_RTREE		14
  	{ .n_name = "_rt_tables"},
  #define N_CLTP		15
  	{ .n_name = "_cltb"},
  #define N_CLTPSTAT	16
  	{ .n_name = "_cltpstat"},
  #define	N_NFILE		17
  	{ .n_name = "_nfile" },
  #define	N_FILE		18
  	{ .n_name = "_file" },
  #define N_MRTSTAT	19
  	{ .n_name = "_mrtstat" },
  #define N_MFCTABLE	20
  	{ .n_name = "_mfctable" },
  #define N_VIFTABLE	21
  	{ .n_name = "_viftable" },
  #define N_IPX		22
  	{ .n_name = "_ipxpcb"},
  #define N_IPXSTAT	23
  	{ .n_name = "_ipxstat"},
  #define N_SPXSTAT	24
  	{ .n_name = "_spx_istat"},
  #define N_NGSOCKS	25
  	{ .n_name = "_ngsocklist"},
  #define N_IP6STAT	26
  	{ .n_name = "_ip6stat" },
  #define N_ICMP6STAT	27
  	{ .n_name = "_icmp6stat" },
  #define N_IPSECSTAT	28
  	{ .n_name = "_ipsecstat" },
  #define N_IPSEC6STAT	29
  	{ .n_name = "_ipsec6stat" },
  #define N_PIM6STAT	30
  	{ .n_name = "_pim6stat" },
  #define N_MRT6PROTO	31
  	{ .n_name = "_ip6_mrtproto" },
  #define N_MRT6STAT	32
  	{ .n_name = "_mrt6stat" },
  #define N_MF6CTABLE	33
  	{ .n_name = "_mf6ctable" },
  #define N_MIF6TABLE	34
  	{ .n_name = "_mif6table" },
  #define N_PFKEYSTAT	35
  	{ .n_name = "_pfkeystat" },
  #define N_MBSTAT	36
  	{ .n_name = "_mbstat" },
  #define N_MBTYPES	37
  	{ .n_name = "_mbtypes" },
  #define N_NMBCLUSTERS	38
  	{ .n_name = "_nmbclusters" },
  #define N_NMBUFS	39
  	{ .n_name = "_nmbufs" },
  #define	N_RTTRASH	40
  	{ .n_name = "_rttrash" },
  #define	N_NCPUS		41
  	{ .n_name = "_ncpus" },
  #define	N_CARPSTAT	42
  	{ .n_name = "_carpstats" },
  	{ .n_name = NULL },
  };
  
  struct protox {
  	u_char	pr_index;		/* index into nlist of cb head */
  	u_char	pr_sindex;		/* index into nlist of stat block */
  	u_char	pr_wanted;		/* 1 if wanted, 0 otherwise */
  	void	(*pr_cblocks)(u_long, const char *, int);
  					/* control blocks printing routine */
  	void	(*pr_stats)(u_long, const char *, int);
  					/* statistics printing routine */
  	void	(*pr_istats)(char *);	/* per/if statistics printing routine */
  	const char *pr_name;		/* well-known name */
  	u_int	pr_usesysctl;		/* true if we use sysctl, not kvm */
  } protox[] = {
  	{ -1,		-1,		1,	protopr,
  	  tcp_stats,	NULL,		"tcp",	IPPROTO_TCP },
  	{ -1,		-1,		1,	protopr,
  	  udp_stats,	NULL,		"udp",	IPPROTO_UDP },
  	{ -1,		-1,		1,	protopr,
  	  NULL,		NULL,		"divert",IPPROTO_DIVERT },
  	{ -1,		-1,		1,	protopr,
  	  ip_stats,	NULL,		"ip",	IPPROTO_RAW },
  	{ -1,		-1,		1,	protopr,
  	  icmp_stats,	NULL,		"icmp",	IPPROTO_ICMP },
  	{ -1,		-1,		1,	protopr,
  	  igmp_stats,	NULL,		"igmp",	IPPROTO_IGMP },
  #ifdef IPSEC
  	{ -1,		N_IPSECSTAT,	1,	0,
  	  ipsec_stats,	NULL,		"ipsec",	0},
  #endif
          { -1,           N_CARPSTAT,     1,      0,
            carp_stats,   NULL,           "carp",         0},
  	{ -1,		-1,		0,	0,
  	  0,		NULL,		NULL,		0}
  };
  
  #ifdef INET6
  struct protox ip6protox[] = {
  	{ -1,		-1,		1,	protopr,
  	  tcp_stats,	NULL,		"tcp",	IPPROTO_TCP },
  	{ -1,		-1,		1,	protopr,
  	  udp_stats,	NULL,		"udp",	IPPROTO_UDP },
  	{ -1,		N_IP6STAT,	1,	protopr,
  	  ip6_stats,	ip6_ifstats,	"ip6",	IPPROTO_RAW },
  	{ -1,		N_ICMP6STAT,	1,	protopr,
  	  icmp6_stats,	icmp6_ifstats,	"icmp6",IPPROTO_ICMPV6 },
  #ifdef IPSEC
  	{ -1,		N_IPSEC6STAT,	1,	0,
  	  ipsec_stats,	NULL,		"ipsec6",0 },
  #endif
  #ifdef notyet
  	{ -1,		N_PIM6STAT,	1,	0,
  	  pim6_stats,	NULL,		"pim6",	0 },
  #endif
  	{ -1,		-1,		1,	0,
  	  rip6_stats,	NULL,		"rip6",	0 },
  	{ -1,		-1,		1,	protopr,
  	  pim_stats,	NULL,		"pim",	IPPROTO_PIM },
  	{ -1,		-1,		0,	0,
  	  0,		NULL,		0,	0 }
  };
  #endif /*INET6*/
  
  #ifdef IPSEC
  struct protox pfkeyprotox[] = {
  	{ -1,		N_PFKEYSTAT,	1,	0,
  	  pfkey_stats,	NULL,		"pfkey", 0 },
  	{ -1,		-1,		0,	0,
  	  0,		NULL,		0,	0 }
  };
  #endif
  
  struct protox netgraphprotox[] = {
  	{ N_NGSOCKS,	-1,		1,	netgraphprotopr,
  	  NULL,		NULL,		"ctrl",	0 },
  	{ N_NGSOCKS,	-1,		1,	netgraphprotopr,
  	  NULL,		NULL,		"data",	0 },
  	{ -1,		-1,		0,	0,
  	  0,		NULL,		NULL,	0 }
  };
  
  struct protox ipxprotox[] = {
  	{ N_IPX,	N_IPXSTAT,	1,	ipxprotopr,
  	  ipx_stats,	NULL,		"ipx",	0 },
  	{ N_IPX,	N_SPXSTAT,	1,	ipxprotopr,
  	  spx_stats,	NULL,		"spx",	0 },
  	{ -1,		-1,		0,	0,
  	  0,		NULL,		0,	0 }
  };
  
  #ifdef ISO
  struct protox isoprotox[] = {
  	{ ISO_TP,	N_TPSTAT,	1,	iso_protopr,
  	  tp_stats,	NULL,		"tp" },
  	{ N_CLTP,	N_CLTPSTAT,	1,	iso_protopr,
  	  cltp_stats,	NULL,		"cltp" },
  	{ -1,		N_CLNPSTAT,	1,	 0,
  	  clnp_stats,	NULL,		"clnp"},
  	{ -1,		N_ESISSTAT,	1,	 0,
  	  esis_stats,	NULL,		"esis"},
  	{ -1,		-1,		0,	0,
  	  0,		NULL,		0 }
  };
  #endif
  
  struct protox *protoprotox[] = {
  					 protox,
  #ifdef INET6
  					 ip6protox,
  #endif
  #ifdef IPSEC
  					 pfkeyprotox,
  #endif
  					 ipxprotox,
  #ifdef ISO
  					 isoprotox, 
  #endif
  					 NULL };
  
  static void printproto (struct protox *, const char *, u_long);
  static void usage (void);
  static struct protox *name2protox (char *);
  static struct protox *knownname (char *);
  
  static kvm_t *kvmd;
  static char *nlistf = NULL, *memf = NULL;
  
  int	Aflag;		/* show addresses of protocol control block */
  int	aflag;		/* show all sockets (including servers) */
  int	bflag;		/* show i/f total bytes in/out */
  int	cpuflag = -1;	/* dump route table from specific cpu */
  int	dflag;		/* show i/f dropped packets */
  int	gflag;		/* show group (multicast) routing or stats */
  int	iflag;		/* show interfaces */
  int	Lflag;		/* show size of listen queues */
  int	mflag;		/* show memory stats */
  int	Pflag;		/* show more protocol info (go past 80 columns) */
  int	numeric_addr;	/* show addresses numerically */
  int	numeric_port;	/* show ports numerically */
  static int pflag;	/* show given protocol */
  int	rflag;		/* show routing tables (or routing stats) */
  int	sflag;		/* show protocol statistics */
  int	tflag;		/* show i/f watchdog timers */
  int	Bflag;		/* show buffer limit instead of buffer use */
  int	Wflag;		/* wide display */
  int	zflag;		/* zero stats */
  
  int	interval;	/* repeat interval for i/f stats */
  
  char	*interface;	/* desired i/f for stats, or NULL for all i/fs */
  int	unit;		/* unit number for above */
  
  int	af;		/* address family */
  
  int
  main(int argc, char **argv)
  {
  	struct protox *tp = NULL;  /* for printing cblocks & stats */
  	int ch;
  	int n;
  
  	af = AF_UNSPEC;
  
  	while ((ch = getopt(argc, argv, "Aabc:df:gI:iLlM:mN:nPp:rSsBtuWw:z")) != -1)
  		switch(ch) {
  		case 'A':
  			Aflag = 1;
  			break;
  		case 'a':
  			aflag = 1;
  			break;
  		case 'b':
  			bflag = 1;
  			break;
  		case 'c':
  			kread(0, 0, 0);
  			kread(nl[N_NCPUS].n_value, (char *)&n, sizeof(n));
  			cpuflag = strtol(optarg, NULL, 0);
  			if (cpuflag < 0 || cpuflag >= n)
  			    errx(1, "cpu %d does not exist", cpuflag);
  			break;
  		case 'd':
  			dflag = 1;
  			break;
  		case 'f':
  			if (strcmp(optarg, "ipx") == 0)
  				af = AF_IPX;
  			else if (strcmp(optarg, "inet") == 0)
  				af = AF_INET;
  #ifdef INET6
  			else if (strcmp(optarg, "inet6") == 0)
  				af = AF_INET6;
  #endif /*INET6*/
  #ifdef INET6
  			else if (strcmp(optarg, "pfkey") == 0)
  				af = PF_KEY;
  #endif /*INET6*/
  			else if (strcmp(optarg, "unix") == 0)
  				af = AF_UNIX;
  			else if (strcmp(optarg, "ng") == 0
  			    || strcmp(optarg, "netgraph") == 0)
  				af = AF_NETGRAPH;
  #ifdef ISO
  			else if (strcmp(optarg, "iso") == 0)
  				af = AF_ISO;
  #endif
  			else if (strcmp(optarg, "link") == 0)
  				af = AF_LINK;
  			else if (strcmp(optarg, "mpls") == 0)
  				af = AF_MPLS;
  			else {
  				errx(1, "%s: unknown address family", optarg);
  			}
  			break;
  		case 'g':
  			gflag = 1;
  			break;
  		case 'I': {
  			char *cp;
  
  			iflag = 1;
  			for (cp = interface = optarg; isalpha(*cp); cp++)
  				continue;
  			unit = atoi(cp);
  			break;
  		}
  		case 'i':
  			iflag = 1;
  			break;
  		case 'L':
  			Lflag = 1;
  			break;
  		case 'M':
  			memf = optarg;
  			break;
  		case 'm':
  			mflag = 1;
  			break;
  		case 'N':
  			nlistf = optarg;
  			break;
  		case 'n':
  			numeric_addr = numeric_port = 1;
  			break;
  		case 'P':
  			Pflag = 1;
  			break;
  		case 'p':
  			if ((tp = name2protox(optarg)) == NULL) {
  				errx(1, 
  				     "%s: unknown or uninstrumented protocol",
  				     optarg);
  			}
  			pflag = 1;
  			break;
  		case 'r':
  			rflag = 1;
  			break;
  		case 's':
  			++sflag;
  			break;
  		case 'S':
  			numeric_addr = 1;
  			break;
  		case 'B':
  			Bflag = 1;
  			break;
  		case 't':
  			tflag = 1;
  			break;
  		case 'u':
  			af = AF_UNIX;
  			break;
  		case 'W':
  		case 'l':
  			Wflag = 1;
  			break;
  		case 'w':
  			interval = atoi(optarg);
  			iflag = 1;
  			break;
  		case 'z':
  			zflag = 1;
  			break;
  		case '?':
  		default:
  			usage();
  		}
  	argv += optind;
  	argc -= optind;
  
  #define	BACKWARD_COMPATIBILITY
  #ifdef	BACKWARD_COMPATIBILITY
  	if (*argv) {
  		if (isdigit(**argv)) {
  			interval = atoi(*argv);
  			if (interval <= 0)
  				usage();
  			++argv;
  			iflag = 1;
  		}
  		if (*argv) {
  			nlistf = *argv;
  			if (*++argv)
  				memf = *argv;
  		}
  	}
  #endif
  
  	/*
  	 * Discard setgid privileges if not the running kernel so that bad
  	 * guys can't print interesting stuff from kernel memory.
  	 */
  	if (nlistf != NULL || memf != NULL)
  		setgid(getgid());
  
  	if (mflag) {
  		if (memf != NULL) {
  			if (kread(0, 0, 0) == 0)
  				mbpr(nl[N_MBSTAT].n_value,
  				    nl[N_MBTYPES].n_value,
  				    nl[N_NMBCLUSTERS].n_value,
  				    nl[N_NMBUFS].n_value,
  				    nl[N_NCPUS].n_value);
  		} else {
  			mbpr(0, 0, 0, 0, 0);
  		}
  		exit(0);
  	}
  #if 0
  	/*
  	 * Keep file descriptors open to avoid overhead
  	 * of open/close on each call to get* routines.
  	 */
  	sethostent(1);
  	setnetent(1);
  #else
  	/*
  	 * This does not make sense any more with DNS being default over
  	 * the files.  Doing a setXXXXent(1) causes a tcp connection to be
  	 * used for the queries, which is slower.
  	 */
  #endif
  	if (iflag && !sflag) {
  		kread(0, 0, 0);
  		intpr(interval, nl[N_IFNET].n_value, NULL, nl[N_NCPUS].n_value);
  		exit(0);
  	}
  	if (rflag) {
  		kread(0, 0, 0);
  		if (sflag)
  			rt_stats();
  		else
  			routepr(nl[N_RTREE].n_value);
  		exit(0);
  	}
  	if (gflag) {
  		kread(0, 0, 0);
  		if (sflag) {
  			if (af == AF_INET || af == AF_UNSPEC)
  				mrt_stats(nl[N_MRTSTAT].n_value);
  #ifdef INET6
  			if (af == AF_INET6 || af == AF_UNSPEC)
  				mrt6_stats(nl[N_MRT6STAT].n_value);
  #endif
  		} else {
  			if (af == AF_INET || af == AF_UNSPEC)
  				mroutepr(nl[N_MFCTABLE].n_value,
  					 nl[N_VIFTABLE].n_value);
  #ifdef INET6
  			if (af == AF_INET6 || af == AF_UNSPEC)
  				mroute6pr(nl[N_MF6CTABLE].n_value,
  					  nl[N_MIF6TABLE].n_value);
  #endif
  		}
  		exit(0);
  	}
  
  	kread(0, 0, 0);
  	if (tp) {
  		printproto(tp, tp->pr_name, nl[N_NCPUS].n_value);
  		exit(0);
  	}
  	if (af == AF_INET || af == AF_UNSPEC)
  		for (tp = protox; tp->pr_name; tp++)
  			printproto(tp, tp->pr_name, nl[N_NCPUS].n_value);
  #ifdef INET6
  	if (af == AF_INET6 || af == AF_UNSPEC)
  		for (tp = ip6protox; tp->pr_name; tp++)
  			printproto(tp, tp->pr_name, nl[N_NCPUS].n_value);
  #endif /*INET6*/
  #ifdef IPSEC
  	if (af == PF_KEY || af == AF_UNSPEC)
  		for (tp = pfkeyprotox; tp->pr_name; tp++)
  			printproto(tp, tp->pr_name, nl[N_NCPUS].n_value);
  #endif /*IPSEC*/
  	if (af == AF_IPX || af == AF_UNSPEC) {
  		kread(0, 0, 0);
  		for (tp = ipxprotox; tp->pr_name; tp++)
  			printproto(tp, tp->pr_name, nl[N_NCPUS].n_value);
  	}
  	if (af == AF_NETGRAPH || af == AF_UNSPEC)
  		for (tp = netgraphprotox; tp->pr_name; tp++)
  			printproto(tp, tp->pr_name, nl[N_NCPUS].n_value);
  #ifdef ISO
  	if (af == AF_ISO || af == AF_UNSPEC)
  		for (tp = isoprotox; tp->pr_name; tp++)
  			printproto(tp, tp->pr_name, nl[N_NCPUS].n_value);
  #endif
  	if ((af == AF_UNIX || af == AF_UNSPEC) && !Lflag && !sflag)
  		unixpr();
  	exit(0);
  }
  
  /*
   * Print out protocol statistics or control blocks (per sflag).
   * If the interface was not specifically requested, and the symbol
   * is not in the namelist, ignore this one.
   */
  static void
  printproto(struct protox *tp, const char *name, u_long ncpusaddr)
  {
  	void (*pr)(u_long, const char *, int);
  	u_long off;
  
  	if (sflag) {
  		if (iflag) {
  			if (tp->pr_istats)
  				intpr(interval, nl[N_IFNET].n_value,
  				      tp->pr_istats, ncpusaddr);
  			else if (pflag)
  				printf("%s: no per-interface stats routine\n",
  				    tp->pr_name);
  			return;
  		}
  		else {
  			pr = tp->pr_stats;
  			if (!pr) {
  				if (pflag)
  					printf("%s: no stats routine\n",
  					    tp->pr_name);
  				return;
  			}
  			off = tp->pr_usesysctl ? tp->pr_usesysctl 
  				: nl[tp->pr_sindex].n_value;
  		}
  	} else {
  		pr = tp->pr_cblocks;
  		if (!pr) {
  			if (pflag)
  				printf("%s: no PCB routine\n", tp->pr_name);
  			return;
  		}
  		off = tp->pr_usesysctl ? tp->pr_usesysctl
  			: nl[tp->pr_index].n_value;
  	}
  	if (pr != NULL && (off || af != AF_UNSPEC))
  		(*pr)(off, name, af);
  }
  
  /*
   * Read kernel memory, return 0 on success.
   */
  int
  kread(u_long addr, char *buf, int size)
  {
  	if (kvmd == NULL) {
  		/*
  		 * XXX.
  		 */
  		kvmd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY, buf);
  		if (kvmd != NULL) {
  			if (kvm_nlist(kvmd, nl) < 0) {
  				if(nlistf)
  					errx(1, "%s: kvm_nlist: %s", nlistf,
  					     kvm_geterr(kvmd));
  				else
  					errx(1, "kvm_nlist: %s", kvm_geterr(kvmd));
  			}
  
  			if (nl[0].n_type == 0) {
  				if(nlistf)
  					errx(1, "%s: no namelist", nlistf);
  				else
  					errx(1, "no namelist");
  			}
  		} else {
  			warnx("kvm not available");
  			return(-1);
  		}
  	}
  	if (!buf)
  		return (0);
  	if (kvm_read(kvmd, addr, buf, size) != size) {
  		warnx("%s", kvm_geterr(kvmd));
  		return (-1);
  	}
  	return (0);
  }
  
  const char *
  plural(int n)
  {
  	return (n != 1 ? "s" : "");
  }
  
  const char *
  plurales(int n)
  {
  	return (n != 1 ? "es" : "");
  }
  
  /*
   * Find the protox for the given "well-known" name.
   */
  static struct protox *
  knownname(char *name)
  {
  	struct protox **tpp, *tp;
  
  	for (tpp = protoprotox; *tpp; tpp++)
  		for (tp = *tpp; tp->pr_name; tp++)
  			if (strcmp(tp->pr_name, name) == 0)
  				return (tp);
  	return (NULL);
  }
  
  /*
   * Find the protox corresponding to name.
   */
  static struct protox *
  name2protox(char *name)
  {
  	struct protox *tp;
  	char **alias;			/* alias from p->aliases */
  	struct protoent *p;
  
  	/*
  	 * Try to find the name in the list of "well-known" names. If that
  	 * fails, check if name is an alias for an Internet protocol.
  	 */
  	if ((tp = knownname(name)) != NULL)
  		return (tp);
  
  	setprotoent(1);			/* make protocol lookup cheaper */
  	while ((p = getprotoent()) != NULL) {
  		/* assert: name not same as p->name */
  		for (alias = p->p_aliases; *alias; alias++)
  			if (strcmp(name, *alias) == 0) {
  				endprotoent();
  				return (knownname(p->p_name));
  			}
  	}
  	endprotoent();
  	return (NULL);
  }
  
  static void
  usage(void)
  {
  	(void)fprintf(stderr, "%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n",
  "usage: netstat [-AaLnPSW] [-c cpu] [-f protocol_family | -p protocol]\n"
  "               [-M core] [-N system]",
  "       netstat -i | -I interface [-aBbdnt] [-f address_family]\n"
  "               [-M core] [-N system]",
  "       netstat -w wait [-I interface] [-d] [-M core] [-N system]",
  "       netstat -s [-s] [-z] [-f protocol_family | -p protocol] [-M core]",
  "       netstat -i | -I interface -s [-f protocol_family | -p protocol]\n"
  "               [-M core] [-N system]",
  "       netstat -m [-M core] [-N system]",
  "       netstat -r [-AanW] [-f address_family] [-M core] [-N system]",
  "       netstat -rs [-s] [-M core] [-N system]",
  "       netstat -g [-W] [-f address_family] [-M core] [-N system]",
  "       netstat -gs [-s] [-f address_family] [-M core] [-N system]");
  	exit(1);
  }
  