diff --git a/usr.bin/kdump/kdump.1 b/usr.bin/kdump/kdump.1
index 1c177efb14a8..3394ff3cf055 100644
--- a/usr.bin/kdump/kdump.1
+++ b/usr.bin/kdump/kdump.1
@@ -1,4 +1,4 @@
-.\"	$NetBSD: kdump.1,v 1.20 2003/07/11 13:05:26 wiz Exp $
+.\"	$NetBSD: kdump.1,v 1.21 2003/07/17 09:05:13 dsl Exp $
 .\"
 .\" Copyright (c) 1990, 1993
 .\"	The Regents of the University of California.  All rights reserved.
@@ -33,7 +33,7 @@
 .\"
 .\"	@(#)kdump.1	8.1 (Berkeley) 6/6/93
 .\"
-.Dd July 11, 2003
+.Dd July 17, 2003
 .Dt KDUMP 1
 .Os
 .Sh NAME
@@ -101,6 +101,8 @@ Display relative timestamps (time since previous entry).
 .It Fl T
 Display absolute timestamps for each entry (seconds since epoch).
 .It Fl t Ar trstr
+Restrict display to the specified set of kernel trace points.
+The default is to display everything in the file.
 See the
 .Fl t
 option of
diff --git a/usr.bin/kdump/kdump.c b/usr.bin/kdump/kdump.c
index 9a42f9932863..1c3e8b3a3f46 100644
--- a/usr.bin/kdump/kdump.c
+++ b/usr.bin/kdump/kdump.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: kdump.c,v 1.57 2003/07/13 18:54:29 dsl Exp $	*/
+/*	$NetBSD: kdump.c,v 1.58 2003/07/17 09:05:13 dsl Exp $	*/
 
 /*-
  * Copyright (c) 1988, 1993
@@ -43,7 +43,7 @@ __COPYRIGHT("@(#) Copyright (c) 1988, 1993\n\
 #if 0
 static char sccsid[] = "@(#)kdump.c	8.4 (Berkeley) 4/28/95";
 #else
-__RCSID("$NetBSD: kdump.c,v 1.57 2003/07/13 18:54:29 dsl Exp $");
+__RCSID("$NetBSD: kdump.c,v 1.58 2003/07/17 09:05:13 dsl Exp $");
 #endif
 #endif /* not lint */
 
@@ -100,7 +100,7 @@ static const char *linux_ptrace_ops[] = {
 
 int	main __P((int, char **));
 int	fread_tail __P((char *, int, int));
-void	dumpheader __P((struct ktr_header *));
+int	dumpheader __P((struct ktr_header *));
 void	ioctldecode __P((u_long));
 void	ktrsyscall __P((struct ktr_syscall *));
 void	ktrsysret __P((struct ktr_sysret *, int));
@@ -116,6 +116,8 @@ void	eprint __P((int));
 void	rprint __P((register_t));
 char	*ioctlname __P((long));
 static const char *signame __P((long, int));
+static void hexdump_buf(const void *, int);
+static void visdump_buf(const void *, int, int);
 
 int
 main(argc, argv)
@@ -124,8 +126,10 @@ main(argc, argv)
 {
 	int ch, ktrlen, size;
 	void *m;
-	int trpoints = ALL_POINTS;
+	int trpoints = 0;
+	int trset = 0;
 	const char *emul_name = "netbsd";
+	int col;
 
 	while ((ch = getopt(argc, argv, "e:f:dlm:Nnp:RTt:x")) != -1)
 		switch (ch) {
@@ -160,7 +164,8 @@ main(argc, argv)
 			timestamp = 1;
 			break;
 		case 't':
-			trpoints = getpoints(optarg);
+			trset = 1;
+			trpoints = getpoints(trpoints, optarg);
 			if (trpoints < 0)
 				errx(1, "unknown trace point in %s", optarg);
 			break;
@@ -173,6 +178,9 @@ main(argc, argv)
 	argv += optind;
 	argc -= optind;
 
+	if (!trset)
+		trpoints = ALL_POINTS;
+
 	if (tracefile == NULL) {
 		if (argc == 1) {
 			tracefile = argv[0];
@@ -195,55 +203,63 @@ main(argc, argv)
 	if (!freopen(tracefile, "r", stdin))
 		err(1, "%s", tracefile);
 	while (fread_tail((char *)&ktr_header, sizeof(struct ktr_header), 1)) {
-		if (trpoints & (1<<ktr_header.ktr_type))
-			if (do_pid == -1 || ktr_header.ktr_pid == do_pid)
-				dumpheader(&ktr_header);
+		if (trpoints & (1<<ktr_header.ktr_type)
+		    && (do_pid == -1 || ktr_header.ktr_pid == do_pid))
+			col = dumpheader(&ktr_header);
+		else
+			col = -1;
 		if ((ktrlen = ktr_header.ktr_len) < 0)
 			errx(1, "bogus length 0x%x", ktrlen);
 		if (ktrlen > size) {
-			while(ktrlen > size) size *= 2;
-			m = (void *)realloc(m, size);
+			while (ktrlen > size)
+				size *= 2;
+			m = realloc(m, size);
 			if (m == NULL)
 				errx(1, "realloc: %s", strerror(ENOMEM));
 		}
 		if (ktrlen && fread_tail(m, ktrlen, 1) == 0)
 			errx(1, "data too short");
-		if ((trpoints & (1<<ktr_header.ktr_type)) == 0)
+		if (col == -1)
 			continue;
 
 		/* update context to match currently processed record */
-		if (do_pid != -1 && ktr_header.ktr_pid != do_pid)
-			continue;
 		ectx_sanify(ktr_header.ktr_pid);
 
 		switch (ktr_header.ktr_type) {
 		case KTR_SYSCALL:
-			ktrsyscall((struct ktr_syscall *)m);
+			ktrsyscall(m);
 			break;
 		case KTR_SYSRET:
-			ktrsysret((struct ktr_sysret *)m, ktrlen);
+			ktrsysret(m, ktrlen);
 			break;
 		case KTR_NAMEI:
 			ktrnamei(m, ktrlen);
 			break;
 		case KTR_GENIO:
-			ktrgenio((struct ktr_genio *)m, ktrlen);
+			ktrgenio(m, ktrlen);
 			break;
 		case KTR_PSIG:
-			ktrpsig((struct ktr_psig *)m);
+			ktrpsig(m);
 			break;
 		case KTR_CSW:
-			ktrcsw((struct ktr_csw *)m);
+			ktrcsw(m);
 			break;
 		case KTR_EMUL:
 			ktremul(m, ktrlen, size);
 			break;
 		case KTR_USER:
-			ktruser((struct ktr_user *)m, ktrlen);
+			ktruser(m, ktrlen);
 			break;
 		case KTR_MMSG:
-			ktrmmsg((struct ktr_mmsg *)m, ktrlen);
+			ktrmmsg(m, ktrlen);
 			break;
+		case KTR_EXEC_ARG:
+		case KTR_EXEC_ENV:
+			visdump_buf(m, ktrlen, col);
+			break;
+		default:
+			printf("\n");
+			hexdump_buf(m, ktrlen);
 		}
 		if (tail)
 			(void)fflush(stdout);
@@ -265,13 +281,14 @@ fread_tail(buf, size, num)
 	return (i);
 }
 
-void
+int
 dumpheader(kth)
 	struct ktr_header *kth;
 {
 	char unknown[64], *type;
 	static struct timeval prevtime;
 	struct timeval temp;
+	int col;
 
 	switch (kth->ktr_type) {
 	case KTR_SYSCALL:
@@ -301,22 +318,32 @@ dumpheader(kth)
 	case KTR_MMSG:
 		type = "MMSG";
 		break;
+	case KTR_EXEC_ENV:
+		type = "ENV";
+		break;
+	case KTR_EXEC_ARG:
+		type = "ARG";
+		break;
 	default:
 		(void)sprintf(unknown, "UNKNOWN(%d)", kth->ktr_type);
 		type = unknown;
 	}
 
-	(void)printf("%6d %-8.*s ", kth->ktr_pid, MAXCOMLEN, kth->ktr_comm);
+	col = printf("%6d %-8.*s ", kth->ktr_pid, MAXCOMLEN, kth->ktr_comm);
 	if (timestamp) {
 		if (timestamp == 2) {
-			timersub(&kth->ktr_time, &prevtime, &temp);
+			if (prevtime.tv_sec == 0)
+				temp.tv_sec = temp.tv_usec = 0;
+			else
+				timersub(&kth->ktr_time, &prevtime, &temp);
 			prevtime = kth->ktr_time;
 		} else
 			temp = kth->ktr_time;
-		(void)printf("%ld.%06ld ",
+		col += printf("%ld.%06ld ",
 		    (long int)temp.tv_sec, (long int)temp.tv_usec);
 	}
-	(void)printf("%s  ", type);
+	col += printf("%-4s  ", type);
+	return col;
 }
 
 void
@@ -549,41 +576,34 @@ ktremul(name, len, bufsize)
 }
 
 static void
-hexdump_buf(void *vdp, int datalen)
+hexdump_buf(const void *vdp, int datalen)
 {
 	char chars[16];
-	unsigned char *dp = vdp;
-	int line_len, i, l, c;
+	const unsigned char *dp = vdp;
+	int line_end, off, l, c;
 	char *cp;
 
-	for (; datalen > 0; datalen -= 16) {
-		line_len = 16;
-		printf("    ");
-		if (line_len > datalen)
-			line_len = datalen;
-		cp = chars;
-		l = 0;
-		printf("\t%3.3lx ", (u_long)dp - (u_long)vdp);
-		for (i = 0; i < line_len; i++) {
+	for (off = 0; off < datalen;) {
+		line_end = off + 16;
+		if (line_end > datalen)
+			line_end = datalen;
+		printf("\t%3.3x ", off);
+		for (l = 0, cp = chars; off < line_end; off++) {
 			c = *dp++;
-			if (i == 8)
+			if ((off & 7) == 0)
 				l += printf(" ");
 			l += printf(" %2.2x", c);
 			*cp++ = isgraph(c) ? c : '.';
-		} while (--i);
+		};
 		printf("%*s %.*s\n", 50 - l, "", (int)(cp - chars), chars);
 	}
 }
 
-void
-ktrgenio(ktr, len)
-	struct ktr_genio *ktr;
-	int len;
+static void
+visdump_buf(const void *vdp, int datalen, int col)
 {
-	int datalen = len - sizeof (struct ktr_genio);
-	char *dp = (char *)ktr + sizeof (struct ktr_genio);
+	const unsigned char *dp = vdp;
 	char *cp;
-	int col = 0;
 	int width;
 	char visbuf[5];
 	static int screenwidth = 0;
@@ -597,20 +617,12 @@ ktrgenio(ktr, len)
 		else
 			screenwidth = 80;
 	}
-	printf("fd %d %s %d bytes\n", ktr->ktr_fd,
-		ktr->ktr_rw == UIO_READ ? "read" : "wrote", datalen);
-	if (maxdata == 0)
-		return;
-	if (maxdata > 0 && datalen > maxdata)
-		datalen = maxdata;
-	if (hexdump) {
-		hexdump_buf(dp, datalen);
-		return;
-	}
-	(void)printf("       \"");
-	col = 8;
+
+	(void)printf("\"");
+	col++;
 	for (; datalen > 0; datalen--, dp++) {
-		(void) vis(visbuf, *dp, VIS_CSTYLE, datalen>1?*(dp+1):0);
+		(void)svis(visbuf, *dp, VIS_CSTYLE,
+		    datalen > 1 ? *(dp + 1) : 0, "\"");
 		cp = visbuf;
 		/*
 		 * Keep track of printables and
@@ -626,12 +638,12 @@ ktrgenio(ktr, len)
 			(void)putchar('\n');
 			continue;
 		case '\t':
-			width = 8 - (col&07);
+			width = 8 - (col & 07);
 			break;
 		default:
 			width = strlen(cp);
 		}
-		if (col + width > (screenwidth-2)) {
+		if (col + width > (screenwidth - 2)) {
 			(void)printf("\\\n\t");
 			col = 8;
 		}
@@ -645,6 +657,28 @@ ktrgenio(ktr, len)
 	(void)printf("\"\n");
 }
 
+void
+ktrgenio(ktr, len)
+	struct ktr_genio *ktr;
+	int len;
+{
+	int datalen = len - sizeof (struct ktr_genio);
+	char *dp = (char *)ktr + sizeof (struct ktr_genio);
+
+	printf("fd %d %s %d bytes\n", ktr->ktr_fd,
+		ktr->ktr_rw == UIO_READ ? "read" : "wrote", datalen);
+	if (maxdata == 0)
+		return;
+	if (maxdata > 0 && datalen > maxdata)
+		datalen = maxdata;
+	if (hexdump) {
+		hexdump_buf(dp, datalen);
+		return;
+	}
+	(void)printf("       ");
+	visdump_buf(dp, datalen, 7);
+}
+
 void
 ktrpsig(psig)
 	struct ktr_psig *psig;
diff --git a/usr.bin/ktrace/ktrace.1 b/usr.bin/ktrace/ktrace.1
index cddb201f179c..82f08fe98505 100644
--- a/usr.bin/ktrace/ktrace.1
+++ b/usr.bin/ktrace/ktrace.1
@@ -1,4 +1,4 @@
-.\"	$NetBSD: ktrace.1,v 1.21 2003/05/06 08:22:08 wiz Exp $
+.\"	$NetBSD: ktrace.1,v 1.22 2003/07/17 09:05:11 dsl Exp $
 .\"
 .\" Copyright (c) 1990, 1993
 .\"	The Regents of the University of California.  All rights reserved.
@@ -33,7 +33,7 @@
 .\"
 .\"	@(#)ktrace.1	8.1 (Berkeley) 6/6/93
 .\"
-.Dd May 2, 2003
+.Dd July 17, 2003
 .Dt KTRACE 1
 .Os
 .Sh NAME
@@ -139,7 +139,9 @@ Print at most
 .Ar maxdata
 bytes of data.
 This is used for pointer type arguments, e.g., strings.
-The data will be escaped in C-style.
+The data will be escaped in C-style unless
+.Fl x
+is specified when it will be output in hex and ascii.
 .It Fl o Ar outfile
 Log trace records to
 .Ar outfile .
@@ -162,26 +164,34 @@ The string argument represents the kernel trace points, one per letter.
 The following table equates the letters with the tracepoints:
 .Pp
 .Bl -tag -width flag -compact
+.It Cm A
+trace all tracepoints
+.It Cm a
+trace exec arguments
 .It Cm c
 trace system calls
 .It Cm e
 trace emulation changes
-.It Cm n
-trace namei translations
 .It Cm i
 trace
 .Tn I/O
+.It Cm n
+trace namei translations
+.It Cm m
+trace Mach messages when running Mach binaries with COMPAT_MACH
+(currently limited to i386 and powerpc ports).
 .It Cm s
 trace signal processing
 .It Cm u
 trace user data
-.It Cm m
-trace Mach messages when running Mach binaries with COMPAT_MACH
-(currently limited to i386 and powerpc ports).
+.It Cm v
+trace exec environment
 .It Cm w
 trace context switches
 .It Cm +
 trace the default set of trace points (c, e, i, m, n, s, u)
+.It Cm -
+do not trace following trace points
 .El
 .It Fl e Ar emulation
 If an emulation of a process is unknown,
diff --git a/usr.bin/ktrace/ktrace.c b/usr.bin/ktrace/ktrace.c
index db1c16f9db1b..1510f2e27a9c 100644
--- a/usr.bin/ktrace/ktrace.c
+++ b/usr.bin/ktrace/ktrace.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: ktrace.c,v 1.26 2002/12/09 21:29:27 manu Exp $	*/
+/*	$NetBSD: ktrace.c,v 1.27 2003/07/17 09:05:12 dsl Exp $	*/
 
 /*-
  * Copyright (c) 1988, 1993
@@ -43,7 +43,7 @@ __COPYRIGHT("@(#) Copyright (c) 1988, 1993\n\
 #if 0
 static char sccsid[] = "@(#)ktrace.c	8.2 (Berkeley) 4/28/95";
 #else
-__RCSID("$NetBSD: ktrace.c,v 1.26 2002/12/09 21:29:27 manu Exp $");
+__RCSID("$NetBSD: ktrace.c,v 1.27 2003/07/17 09:05:12 dsl Exp $");
 #endif
 #endif /* not lint */
 
@@ -85,7 +85,7 @@ main(argc, argv)
 	char **argv;
 {
 	enum { NOTSET, CLEAR, CLEARALL } clear;
-	int append, ch, fd, inherit, ops, pid, pidset, synclog, trpoints;
+	int append, ch, fd, trset, ops, pid, pidset, synclog, trpoints;
 	const char *outfile;
 #ifdef KTRUSS
 	const char *infile;
@@ -93,8 +93,8 @@ main(argc, argv)
 #endif
 
 	clear = NOTSET;
-	append = ops = pidset = inherit = synclog = 0;
-	trpoints = DEF_POINTS;
+	append = ops = pidset = trset = synclog = 0;
+	trpoints = 0;
 	pid = 0;	/* Appease GCC */
 
 #ifdef KTRUSS
@@ -138,7 +138,7 @@ main(argc, argv)
 			pidset = 1;
 			break;
 		case 'i':
-			inherit = 1;
+			trpoints |= KTRFAC_INHERIT;
 			break;
 #ifdef KTRUSS
 		case 'l':
@@ -170,7 +170,8 @@ main(argc, argv)
 			break;
 #endif
 		case 't':
-			trpoints = getpoints(optarg);
+			trset = 1;
+			trpoints = getpoints(trpoints, optarg);
 			if (trpoints < 0) {
 				warnx("unknown facility in %s", optarg);
 				usage();
@@ -182,9 +183,12 @@ main(argc, argv)
 	argv += optind;
 	argc -= optind;
 
+	if (!trset)
+		trpoints |= clear == NOTSET ? DEF_POINTS : ALL_POINTS;
+
 	if ((pidset && *argv) || (!pidset && !*argv)) {
 #ifdef KTRUSS
-	    if(!infile)
+	    if (!infile)
 #endif
 		usage();
 	}
@@ -204,9 +208,6 @@ main(argc, argv)
 	 */
 	free(malloc(1));
 	
-	if (inherit)
-		trpoints |= KTRFAC_INHERIT;
-
 	(void)signal(SIGSYS, no_ktrace);
 	if (clear != NOTSET) {
 		if (clear == CLEARALL) {
@@ -235,7 +236,7 @@ main(argc, argv)
 			err(1, "exec of '%s' failed", argv[0]);
 		}
 #else
-		(void) do_ktrace(outfile, ops, trpoints, getpid());
+		(void)do_ktrace(outfile, ops, trpoints, getpid());
 		execvp(argv[0], &argv[0]);
 		err(1, "exec of '%s' failed", argv[0]);
 #endif
diff --git a/usr.bin/ktrace/ktrace.h b/usr.bin/ktrace/ktrace.h
index 5dfaea7fb364..731992de2a24 100644
--- a/usr.bin/ktrace/ktrace.h
+++ b/usr.bin/ktrace/ktrace.h
@@ -1,4 +1,4 @@
-/*	$NetBSD: ktrace.h,v 1.11 2002/12/09 21:29:27 manu Exp $	*/
+/*	$NetBSD: ktrace.h,v 1.12 2003/07/17 09:05:12 dsl Exp $	*/
 
 /*-
  * Copyright (c) 1988, 1993
@@ -39,12 +39,12 @@
 		  KTRFAC_GENIO | KTRFAC_PSIG | KTRFAC_EMUL | KTRFAC_USER | \
 		  KTRFAC_MMSG)
 
-#define ALL_POINTS (DEF_POINTS | KTRFAC_CSW)
+#define ALL_POINTS KTRFAC_MASK
 
 #define DEF_TRACEFILE	"ktrace.out"
 
 #include <sys/cdefs.h>
 
-int	 getpoints __P((char *));
-char	*ioctlname __P((long));
-void	dumpfile __P((const char *, int, int));
+int	getpoints(int, char *);
+char	*ioctlname(long);
+void	dumpfile(const char *, int, int);
diff --git a/usr.bin/ktrace/subr.c b/usr.bin/ktrace/subr.c
index 95f9463b784a..88098eab2fc4 100644
--- a/usr.bin/ktrace/subr.c
+++ b/usr.bin/ktrace/subr.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: subr.c,v 1.9 2002/12/09 21:29:27 manu Exp $	*/
+/*	$NetBSD: subr.c,v 1.10 2003/07/17 09:05:12 dsl Exp $	*/
 
 /*-
  * Copyright (c) 1988, 1993
@@ -38,7 +38,7 @@
 #if 0
 static char sccsid[] = "@(#)subr.c	8.2 (Berkeley) 4/28/95";
 #else
-__RCSID("$NetBSD: subr.c,v 1.9 2002/12/09 21:29:27 manu Exp $");
+__RCSID("$NetBSD: subr.c,v 1.10 2003/07/17 09:05:12 dsl Exp $");
 #endif
 #endif /* not lint */
 
@@ -54,44 +54,68 @@ __RCSID("$NetBSD: subr.c,v 1.9 2002/12/09 21:29:27 manu Exp $");
 #include "ktrace.h"
 
 int
-getpoints(s)
-	char *s;
+getpoints(int facs, char *s)
 {
-	int facs = 0;
+	int fac;
+	int add = 1;
 
-	while (*s) {
-		switch(*s) {
+	/* Make -t-x equivalent to -t+-x since that is rather more useful */
+	if (*s == '-' && (facs & ALL_POINTS) == 0)
+		facs |= DEF_POINTS;
+
+	for (;;) {
+		switch (*s++) {
+		case 0:
+			return facs;
+		case 'A':
+			fac = ALL_POINTS;
+			break;
+		case 'a':
+			fac = KTRFAC_EXEC_ARG;
+			break;
 		case 'c':
-			facs |= KTRFAC_SYSCALL | KTRFAC_SYSRET;
+			fac = KTRFAC_SYSCALL | KTRFAC_SYSRET;
 			break;
 		case 'e':
-			facs |= KTRFAC_EMUL;
-			break;
-		case 'n':
-			facs |= KTRFAC_NAMEI;
+			fac = KTRFAC_EMUL;
 			break;
 		case 'i':
-			facs |= KTRFAC_GENIO;
+			fac = KTRFAC_GENIO;
 			break;
-		case 's':
-			facs |= KTRFAC_PSIG;
-			break;
-		case 'u':
-			facs |= KTRFAC_USER;
+		case 'n':
+			fac = KTRFAC_NAMEI;
 			break;
 		case 'm':
-			facs |= KTRFAC_MMSG;
+			fac = KTRFAC_MMSG;
+			break;
+		case 's':
+			fac = KTRFAC_PSIG;
+			break;
+		case 'u':
+			fac = KTRFAC_USER;
+			break;
+		case 'v':
+			fac = KTRFAC_EXEC_ENV;
 			break;
 		case 'w':
-			facs |= KTRFAC_CSW;
+			fac = KTRFAC_CSW;
 			break;
 		case '+':
-			facs |= DEF_POINTS;
+			if (!add) {
+				add = 1;
+				continue;
+			}
+			fac = DEF_POINTS;
 			break;
+		case '-':
+			add = 0;
+			continue;
 		default:
 			return (-1);
 		}
-		s++;
+		if (add)
+			facs |= fac;
+		else
+			facs &= ~fac;
 	}
-	return (facs);
 }