- Make truss thread-aware.

Approved by:	kib (mentor)
MFC after:	2 weeks

14 files changed, 804 insertions, 721 deletions

diff --git a/usr.bin/truss/amd64-fbsd.c b/usr.bin/truss/amd64-fbsd.c
index 4ded727..516c4d2 100644
--- a/usr.bin/truss/amd64-fbsd.c
+++ b/usr.bin/truss/amd64-fbsd.c
@@ -62,8 +62,6 @@ static const char rcsid[] =
 #include "syscall.h"
 #include "extern.h"
 
-static int cpid = -1;
-
 #include "syscalls.h"
 
 static int nsyscalls = sizeof(syscallnames) / sizeof(syscallnames[0]);
@@ -77,30 +75,35 @@ static int nsyscalls = sizeof(syscallnames) / sizeof(syscallnames[0]);
  * 'struct syscall' describes the system call; it may be NULL, however,
  * if we don't know about this particular system call yet.
  */
-static struct freebsd_syscall {
+struct freebsd_syscall {
 	struct syscall *sc;
 	const char *name;
 	int number;
 	unsigned long *args;
 	int nargs;	/* number of arguments -- *not* number of words! */
 	char **s_args;	/* the printable arguments */
-} fsc;
+};
+
+static struct freebsd_syscall *
+alloc_fsc(void)
+{
+
+	return (malloc(sizeof(struct freebsd_syscall)));
+}
 
 /* Clear up and free parts of the fsc structure. */
-static __inline void
-clear_fsc(void)
+static void
+free_fsc(struct freebsd_syscall *fsc)
 {
 	int i;
 
-	if (fsc.args)
-		free(fsc.args);
-	if (fsc.s_args) {
-		for (i = 0; i < fsc.nargs; i++)
-			if (fsc.s_args[i])
-				free(fsc.s_args[i]);
-		free(fsc.s_args);
+	free(fsc->args);
+	if (fsc->s_args) {
+		for (i = 0; i < fsc->nargs; i++)
+			free(fsc->s_args[i]);
+		free(fsc->s_args);
 	}
-	memset(&fsc, 0, sizeof(fsc));
+	free(fsc);
 }
 
 /*
@@ -115,14 +118,14 @@ amd64_syscall_entry(struct trussinfo *trussinfo, int nargs)
 {
 	struct ptrace_io_desc iorequest;
 	struct reg regs;
+	struct freebsd_syscall *fsc;
 	struct syscall *sc;
+	lwpid_t tid;
 	int i, reg, syscall_num;
 
-	clear_fsc();
-
-	cpid = trussinfo->curthread->tid;
+	tid = trussinfo->curthread->tid;
 
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
 		return;
 	}
@@ -142,57 +145,60 @@ amd64_syscall_entry(struct trussinfo *trussinfo, int nargs)
 		break;
 	}
 
-	fsc.number = syscall_num;
-	fsc.name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
+	fsc = alloc_fsc();
+	if (fsc == NULL)
+		return;
+	fsc->number = syscall_num;
+	fsc->name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
 	    NULL : syscallnames[syscall_num];
-	if (!fsc.name) {
+	if (!fsc->name) {
 		fprintf(trussinfo->outfile, "-- UNKNOWN SYSCALL %d --\n",
 		    syscall_num);
 	}
 
-	if (fsc.name && (trussinfo->flags & FOLLOWFORKS) &&
-	    (strcmp(fsc.name, "fork") == 0 ||
-	    strcmp(fsc.name, "rfork") == 0||
-	    strcmp(fsc.name, "vfork") == 0))
+	if (fsc->name && (trussinfo->flags & FOLLOWFORKS) &&
+	    (strcmp(fsc->name, "fork") == 0 ||
+	    strcmp(fsc->name, "rfork") == 0 ||
+	    strcmp(fsc->name, "vfork") == 0))
 		trussinfo->curthread->in_fork = 1;
 
 	if (nargs == 0)
 		return;
 
-	fsc.args = malloc((1 + nargs) * sizeof(unsigned long));
+	fsc->args = malloc((1 + nargs) * sizeof(unsigned long));
 	for (i = 0; i < nargs && reg < 6; i++, reg++) {
 		switch (reg) {
-		case 0: fsc.args[i] = regs.r_rdi; break;
-		case 1: fsc.args[i] = regs.r_rsi; break;
-		case 2: fsc.args[i] = regs.r_rdx; break;
-		case 3: fsc.args[i] = regs.r_rcx; break;
-		case 4: fsc.args[i] = regs.r_r8; break;
-		case 5: fsc.args[i] = regs.r_r9; break;
+		case 0: fsc->args[i] = regs.r_rdi; break;
+		case 1: fsc->args[i] = regs.r_rsi; break;
+		case 2: fsc->args[i] = regs.r_rdx; break;
+		case 3: fsc->args[i] = regs.r_rcx; break;
+		case 4: fsc->args[i] = regs.r_r8; break;
+		case 5: fsc->args[i] = regs.r_r9; break;
 		}
 	}
 	if (nargs > i) {
 		iorequest.piod_op = PIOD_READ_D;
 		iorequest.piod_offs = (void *)(regs.r_rsp + sizeof(register_t));
-		iorequest.piod_addr = &fsc.args[i];
+		iorequest.piod_addr = &fsc->args[i];
 		iorequest.piod_len = (nargs - i) * sizeof(register_t);
-		ptrace(PT_IO, cpid, (caddr_t)&iorequest, 0);
+		ptrace(PT_IO, tid, (caddr_t)&iorequest, 0);
 		if (iorequest.piod_len == 0)
 			return;
 	}
 
-	sc = get_syscall(fsc.name);
+	sc = get_syscall(fsc->name);
 	if (sc)
-		fsc.nargs = sc->nargs;
+		fsc->nargs = sc->nargs;
 	else {
 #if DEBUG
 		fprintf(trussinfo->outfile, "unknown syscall %s -- setting "
-		    "args to %d\n", fsc.name, nargs);
+		    "args to %d\n", fsc->name, nargs);
 #endif
-		fsc.nargs = nargs;
+		fsc->nargs = nargs;
 	}
 
-	fsc.s_args = calloc(1, (1 + fsc.nargs) * sizeof(char *));
-	fsc.sc = sc;
+	fsc->s_args = calloc(1, (1 + fsc->nargs) * sizeof(char *));
+	fsc->sc = sc;
 
 	/*
 	 * At this point, we set up the system call arguments.
@@ -202,19 +208,19 @@ amd64_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	 * passed in *and* out, however.
 	 */
 
-	if (fsc.name) {
+	if (fsc->name) {
 #if DEBUG
-		fprintf(stderr, "syscall %s(", fsc.name);
+		fprintf(stderr, "syscall %s(", fsc->name);
 #endif
-		for (i = 0; i < fsc.nargs; i++) {
+		for (i = 0; i < fsc->nargs; i++) {
 #if DEBUG
 			fprintf(stderr, "0x%lx%s", sc ?
-			    fsc.args[sc->args[i].offset] : fsc.args[i],
-			    i < (fsc.nargs - 1) ? "," : "");
+			    fsc->args[sc->args[i].offset] : fsc->args[i],
+			    i < (fsc->nargs - 1) ? "," : "");
 #endif
 			if (sc && !(sc->args[i].type & OUT)) {
-				fsc.s_args[i] = print_arg(&sc->args[i],
-				    fsc.args, 0, trussinfo);
+				fsc->s_args[i] = print_arg(&sc->args[i],
+				    fsc->args, 0, trussinfo);
 			}
 		}
 #if DEBUG
@@ -226,30 +232,29 @@ amd64_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	fprintf(trussinfo->outfile, "\n");
 #endif
 
-	if (fsc.name != NULL && (strcmp(fsc.name, "execve") == 0 ||
-	    strcmp(fsc.name, "exit") == 0)) {
+	if (fsc->name != NULL && (strcmp(fsc->name, "execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0)) {
 		/*
 		 * XXX
 		 * This could be done in a more general
 		 * manner but it still wouldn't be very pretty.
 		 */
-		if (strcmp(fsc.name, "execve") == 0) {
+		if (strcmp(fsc->name, "execve") == 0) {
 			if ((trussinfo->flags & EXECVEARGS) == 0) {
-				if (fsc.s_args[1]) {
-					free(fsc.s_args[1]);
-					fsc.s_args[1] = NULL;
+				if (fsc->s_args[1]) {
+					free(fsc->s_args[1]);
+					fsc->s_args[1] = NULL;
 				}
 			}
 			if ((trussinfo->flags & EXECVEENVS) == 0) {
-				if (fsc.s_args[2]) {
-					free(fsc.s_args[2]);
-					fsc.s_args[2] = NULL;
+				if (fsc->s_args[2]) {
+					free(fsc->s_args[2]);
+					fsc->s_args[2] = NULL;
 				}
 			}
 		}
 	}
-
-	return;
+	trussinfo->curthread->fsc = fsc;
 }
 
 /*
@@ -263,16 +268,18 @@ long
 amd64_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 {
 	struct reg regs;
+	struct freebsd_syscall *fsc;
 	struct syscall *sc;
+	lwpid_t tid;
 	long retval;
 	int errorp, i;
 
-	if (fsc.name == NULL)
+	if (trussinfo->curthread->fsc == NULL)
 		return (-1);
 
-	cpid = trussinfo->curthread->tid;
+	tid = trussinfo->curthread->tid;
 
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
 		return (-1);
 	}
@@ -285,10 +292,11 @@ amd64_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 	 * stand some significant cleaning.
 	 */
 
-	sc = fsc.sc;
+	fsc = trussinfo->curthread->fsc;
+	sc = fsc->sc;
 	if (!sc) {
-		for (i = 0; i < fsc.nargs; i++)
-			asprintf(&fsc.s_args[i], "0x%lx", fsc.args[i]);
+		for (i = 0; i < fsc->nargs; i++)
+			asprintf(&fsc->s_args[i], "0x%lx", fsc->args[i]);
 	} else {
 		/*
 		 * Here, we only look for arguments that have OUT masked in --
@@ -303,18 +311,18 @@ amd64_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 				 */
 				if (errorp) {
 					asprintf(&temp, "0x%lx",
-					    fsc.args[sc->args[i].offset]);
+					    fsc->args[sc->args[i].offset]);
 				} else {
 					temp = print_arg(&sc->args[i],
-					    fsc.args, retval, trussinfo);
+					    fsc->args, retval, trussinfo);
 				}
-				fsc.s_args[i] = temp;
+				fsc->s_args[i] = temp;
 			}
 		}
 	}
 
-	if (fsc.name != NULL && (strcmp(fsc.name, "execve") == 0 ||
-	    strcmp(fsc.name, "exit") == 0))
+	if (fsc->name != NULL && (strcmp(fsc->name, "execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0))
 		trussinfo->curthread->in_syscall = 1;
 
 	/*
@@ -322,9 +330,9 @@ amd64_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 	 * but that complicates things considerably.
 	 */
 
-	print_syscall_ret(trussinfo, fsc.name, fsc.nargs, fsc.s_args, errorp,
-	    retval, fsc.sc);
-	clear_fsc();
+	print_syscall_ret(trussinfo, fsc->name, fsc->nargs, fsc->s_args, errorp,
+	    retval, fsc->sc);
+	free_fsc(fsc);
 
 	return (retval);
 }
diff --git a/usr.bin/truss/amd64-fbsd32.c b/usr.bin/truss/amd64-fbsd32.c
index 5cf9f84..72f4295 100644
--- a/usr.bin/truss/amd64-fbsd32.c
+++ b/usr.bin/truss/amd64-fbsd32.c
@@ -62,8 +62,6 @@ static const char rcsid[] =
 #include "syscall.h"
 #include "extern.h"
 
-static int cpid = -1;
-
 #include "freebsd32_syscalls.h"
 
 static int nsyscalls = sizeof(freebsd32_syscallnames) /
@@ -78,7 +76,7 @@ static int nsyscalls = sizeof(freebsd32_syscallnames) /
  * 'struct syscall' describes the system call; it may be NULL, however,
  * if we don't know about this particular system call yet.
  */
-static struct freebsd32_syscall {
+struct freebsd32_syscall {
 	struct syscall *sc;
 	const char *name;
 	int number;
@@ -86,25 +84,29 @@ static struct freebsd32_syscall {
 	unsigned int *args32;
 	int nargs;	/* number of arguments -- *not* number of words! */
 	char **s_args;	/* the printable arguments */
-} fsc;
+};
+
+static struct freebsd32_syscall *
+alloc_fsc(void)
+{
+
+	return (malloc(sizeof(struct freebsd32_syscall)));
+}
 
 /* Clear up and free parts of the fsc structure. */
-static __inline void
-clear_fsc(void)
+static void
+free_fsc(struct freebsd32_syscall *fsc)
 {
 	int i;
 
-	if (fsc.args)
-		free(fsc.args);
-	if (fsc.args32)
-		free(fsc.args32);
-	if (fsc.s_args) {
-		for (i = 0; i < fsc.nargs; i++)
-			if (fsc.s_args[i])
-				free(fsc.s_args[i]);
-		free(fsc.s_args);
+	free(fsc->args);
+	free(fsc->args32);
+	if (fsc->s_args) {
+		for (i = 0; i < fsc->nargs; i++)
+			free(fsc->s_args[i]);
+		free(fsc->s_args);
 	}
-	memset(&fsc, 0, sizeof(fsc));
+	free(fsc);
 }
 
 /*
@@ -119,15 +121,15 @@ amd64_fbsd32_syscall_entry(struct trussinfo *trussinfo, int nargs)
 {
 	struct ptrace_io_desc iorequest;
 	struct reg regs;
+	struct freebsd32_syscall *fsc;
 	struct syscall *sc;
+	lwpid_t tid;
 	unsigned long parm_offset;
 	int i, syscall_num;
 
-	clear_fsc();
-
-	cpid = trussinfo->curthread->tid;
+	tid = trussinfo->curthread->tid;
 
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
 		return;
 	}
@@ -141,60 +143,63 @@ amd64_fbsd32_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	syscall_num = regs.r_rax;
 	switch (syscall_num) {
 	case SYS_syscall:
-		syscall_num = ptrace(PT_READ_D, cpid, (caddr_t)parm_offset, 0);
+		syscall_num = ptrace(PT_READ_D, tid, (caddr_t)parm_offset, 0);
 		parm_offset += sizeof(int);
 		break;
 	case SYS___syscall:
-		syscall_num = ptrace(PT_READ_D, cpid, (caddr_t)parm_offset, 0);
+		syscall_num = ptrace(PT_READ_D, tid, (caddr_t)parm_offset, 0);
 		parm_offset += sizeof(quad_t);
 		break;
 	}
 
-	fsc.number = syscall_num;
-	fsc.name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
+	fsc = alloc_fsc();
+	if (fsc == NULL)
+		return;
+	fsc->number = syscall_num;
+	fsc->name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
 	    NULL : freebsd32_syscallnames[syscall_num];
-	if (!fsc.name) {
+	if (!fsc->name) {
 		fprintf(trussinfo->outfile, "-- UNKNOWN SYSCALL %d --\n",
 		    syscall_num);
 	}
 
-	if (fsc.name && (trussinfo->flags & FOLLOWFORKS) &&
-	    (strcmp(fsc.name, "fork") == 0 ||
-	    strcmp(fsc.name, "rfork") == 0||
-	    strcmp(fsc.name, "vfork") == 0))
+	if (fsc->name && (trussinfo->flags & FOLLOWFORKS) &&
+	    (strcmp(fsc->name, "fork") == 0 ||
+	    strcmp(fsc->name, "rfork") == 0 ||
+	    strcmp(fsc->name, "vfork") == 0))
 		trussinfo->curthread->in_fork = 1;
 
 	if (nargs == 0)
 		return;
 
-	fsc.args32 = malloc((1 + nargs) * sizeof(unsigned int));
+	fsc->args32 = malloc((1 + nargs) * sizeof(unsigned int));
 	iorequest.piod_op = PIOD_READ_D;
 	iorequest.piod_offs = (void *)parm_offset;
-	iorequest.piod_addr = fsc.args32;
+	iorequest.piod_addr = fsc->args32;
 	iorequest.piod_len = (1 + nargs) * sizeof(unsigned int);
-	ptrace(PT_IO, cpid, (caddr_t)&iorequest, 0);
+	ptrace(PT_IO, tid, (caddr_t)&iorequest, 0);
 	if (iorequest.piod_len == 0)
 		return;
 
-	fsc.args = malloc((1 + nargs) * sizeof(unsigned long));
+	fsc->args = malloc((1 + nargs) * sizeof(unsigned long));
 	for (i = 0; i < nargs + 1; i++)
-		 fsc.args[i] = fsc.args32[i];
+		 fsc->args[i] = fsc->args32[i];
 
 	sc = NULL;
-	if (fsc.name)
-		sc = get_syscall(fsc.name);
+	if (fsc->name)
+		sc = get_syscall(fsc->name);
 	if (sc)
-		fsc.nargs = sc->nargs;
+		fsc->nargs = sc->nargs;
 	else {
 #if DEBUG
 		fprintf(trussinfo->outfile, "unknown syscall %s -- setting "
-		    "args to %d\n", fsc.name, nargs);
+		    "args to %d\n", fsc->name, nargs);
 #endif
-		fsc.nargs = nargs;
+		fsc->nargs = nargs;
 	}
 
-	fsc.s_args = calloc(1, (1 + fsc.nargs) * sizeof(char *));
-	fsc.sc = sc;
+	fsc->s_args = calloc(1, (1 + fsc->nargs) * sizeof(char *));
+	fsc->sc = sc;
 
 	/*
 	 * At this point, we set up the system call arguments.
@@ -204,19 +209,19 @@ amd64_fbsd32_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	 * passed in *and* out, however.
 	 */
 
-	if (fsc.name) {
+	if (fsc->name) {
 #if DEBUG
-		fprintf(stderr, "syscall %s(", fsc.name);
+		fprintf(stderr, "syscall %s(", fsc->name);
 #endif
-		for (i = 0; i < fsc.nargs; i++) {
+		for (i = 0; i < fsc->nargs; i++) {
 #if DEBUG
 			fprintf(stderr, "0x%x%s", sc ?
-			    fsc.args[sc->args[i].offset] : fsc.args[i],
-			    i < (fsc.nargs - 1) ? "," : "");
+			    fsc->args[sc->args[i].offset] : fsc->args[i],
+			    i < (fsc->nargs - 1) ? "," : "");
 #endif
 			if (sc && !(sc->args[i].type & OUT)) {
-				fsc.s_args[i] = print_arg(&sc->args[i],
-				    fsc.args, 0, trussinfo);
+				fsc->s_args[i] = print_arg(&sc->args[i],
+				    fsc->args, 0, trussinfo);
 			}
 		}
 #if DEBUG
@@ -228,30 +233,29 @@ amd64_fbsd32_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	fprintf(trussinfo->outfile, "\n");
 #endif
 
-	if (fsc.name != NULL && (strcmp(fsc.name, "freebsd32_execve") == 0||
-	    strcmp(fsc.name, "exit") == 0)) {
+	if (fsc->name != NULL && (strcmp(fsc->name, "freebsd32_execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0)) {
 		/*
 		 * XXX
 		 * This could be done in a more general
 		 * manner but it still wouldn't be very pretty.
 		 */
-		if (strcmp(fsc.name, "freebsd32_execve") == 0) {
+		if (strcmp(fsc->name, "freebsd32_execve") == 0) {
 			if ((trussinfo->flags & EXECVEARGS) == 0) {
-				if (fsc.s_args[1]) {
-					free(fsc.s_args[1]);
-					fsc.s_args[1] = NULL;
+				if (fsc->s_args[1]) {
+					free(fsc->s_args[1]);
+					fsc->s_args[1] = NULL;
 				}
 			}
 			if ((trussinfo->flags & EXECVEENVS) == 0) {
-				if (fsc.s_args[2]) {
-					free(fsc.s_args[2]);
-					fsc.s_args[2] = NULL;
+				if (fsc->s_args[2]) {
+					free(fsc->s_args[2]);
+					fsc->s_args[2] = NULL;
 				}
 			}
 		}
 	}
-
-	return;
+	trussinfo->curthread->fsc = fsc;
 }
 
 /*
@@ -265,16 +269,18 @@ long
 amd64_fbsd32_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 {
 	struct reg regs;
+	struct freebsd32_syscall *fsc;
 	struct syscall *sc;
+	lwpid_t tid;
 	long retval;
 	int errorp, i;
 
-	if (fsc.name == NULL)
+	if (trussinfo->curthread->fsc == NULL)
 		return (-1);
 
-	cpid = trussinfo->curthread->tid;
+	tid = trussinfo->curthread->tid;
 
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
 		return (-1);
 	}
@@ -287,10 +293,11 @@ amd64_fbsd32_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 	 * stand some significant cleaning.
 	 */
 
-	sc = fsc.sc;
+	fsc = trussinfo->curthread->fsc;
+	sc = fsc->sc;
 	if (!sc) {
-		for (i = 0; i < fsc.nargs; i++)
-			asprintf(&fsc.s_args[i], "0x%lx", fsc.args[i]);
+		for (i = 0; i < fsc->nargs; i++)
+			asprintf(&fsc->s_args[i], "0x%lx", fsc->args[i]);
 	} else {
 		/*
 		 * Here, we only look for arguments that have OUT masked in --
@@ -305,18 +312,18 @@ amd64_fbsd32_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 				 */
 				if (errorp) {
 					asprintf(&temp, "0x%lx",
-					    fsc.args[sc->args[i].offset]);
+					    fsc->args[sc->args[i].offset]);
 				} else {
 					temp = print_arg(&sc->args[i],
-					    fsc.args, retval, trussinfo);
+					    fsc->args, retval, trussinfo);
 				}
-				fsc.s_args[i] = temp;
+				fsc->s_args[i] = temp;
 			}
 		}
 	}
 
-	if (fsc.name != NULL && (strcmp(fsc.name, "freebsd32_execve") == 0 ||
-	    strcmp(fsc.name, "exit") == 0))
+	if (fsc->name != NULL && (strcmp(fsc->name, "freebsd32_execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0))
 		trussinfo->curthread->in_syscall = 1;
 
 	/*
@@ -324,9 +331,9 @@ amd64_fbsd32_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 	 * but that complicates things considerably.
 	 */
 
-	print_syscall_ret(trussinfo, fsc.name, fsc.nargs, fsc.s_args, errorp,
-	    retval, fsc.sc);
-	clear_fsc();
+	print_syscall_ret(trussinfo, fsc->name, fsc->nargs, fsc->s_args, errorp,
+	    retval, fsc->sc);
+	free_fsc(fsc);
 
 	return (retval);
 }
diff --git a/usr.bin/truss/amd64-linux32.c b/usr.bin/truss/amd64-linux32.c
index e041b60..2c025a3 100644
--- a/usr.bin/truss/amd64-linux32.c
+++ b/usr.bin/truss/amd64-linux32.c
@@ -59,8 +59,6 @@ static const char rcsid[] =
 #include "syscall.h"
 #include "extern.h"
 
-static int cpid = -1;
-
 #include "linux32_syscalls.h"
 
 static int nsyscalls =
@@ -75,28 +73,34 @@ static int nsyscalls =
  * 'struct syscall' describes the system call; it may be NULL, however,
  * if we don't know about this particular system call yet.
  */
-static struct linux_syscall {
+struct linux_syscall {
 	struct syscall *sc;
 	const char *name;
 	int number;
 	unsigned long args[5];
 	int nargs;	/* number of arguments -- *not* number of words! */
 	char **s_args;	/* the printable arguments */
-} fsc;
+};
+
+static struct linux_syscall *
+alloc_fsc(void)
+{
+
+	return (malloc(sizeof(struct linux_syscall)));
+}
 
 /* Clear up and free parts of the fsc structure. */
-static __inline void
-clear_fsc(void)
+static void
+free_fsc(struct linux_syscall *fsc)
 {
 	int i;
 
-	if (fsc.s_args) {
-		for (i = 0; i < fsc.nargs; i++)
-			if (fsc.s_args[i])
-				free(fsc.s_args[i]);
-		free(fsc.s_args);
+	if (fsc->s_args) {
+		for (i = 0; i < fsc->nargs; i++)
+			free(fsc->s_args[i]);
+		free(fsc->s_args);
 	}
-	memset(&fsc, 0, sizeof(fsc));
+	free(fsc);
 }
 
 /*
@@ -110,31 +114,34 @@ void
 amd64_linux32_syscall_entry(struct trussinfo *trussinfo, int nargs)
 {
 	struct reg regs;
+	struct linux_syscall *fsc;
 	struct syscall *sc;
+	lwpid_t tid;
 	int i, syscall_num;
 
-	clear_fsc();
-
-	cpid = trussinfo->curthread->tid;
+	tid = trussinfo->curthread->tid;
 
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
 		return;
 	}
 
 	syscall_num = regs.r_rax;
 
-	fsc.number = syscall_num;
-	fsc.name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
+	fsc = alloc_fsc();
+	if (fsc == NULL)
+		return;
+	fsc->number = syscall_num;
+	fsc->name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
 	    NULL : linux32_syscallnames[syscall_num];
-	if (!fsc.name) {
+	if (!fsc->name) {
 		fprintf(trussinfo->outfile, "-- UNKNOWN SYSCALL %d --\n",
 		    syscall_num);
 	}
 
-	if (fsc.name && (trussinfo->flags & FOLLOWFORKS) &&
-	    (strcmp(fsc.name, "linux_fork") == 0||
-	    strcmp(fsc.name, "linux_vfork") == 0))
+	if (fsc->name && (trussinfo->flags & FOLLOWFORKS) &&
+	    (strcmp(fsc->name, "linux_fork") == 0 ||
+	    strcmp(fsc->name, "linux_vfork") == 0))
 		trussinfo->curthread->in_fork = 1;
 
 	if (nargs == 0)
@@ -148,25 +155,25 @@ amd64_linux32_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	 * that have more than five arguments?
 	 */
 
-	fsc.args[0] = regs.r_rbx;
-	fsc.args[1] = regs.r_rcx;
-	fsc.args[2] = regs.r_rdx;
-	fsc.args[3] = regs.r_rsi;
-	fsc.args[4] = regs.r_rdi;
+	fsc->args[0] = regs.r_rbx;
+	fsc->args[1] = regs.r_rcx;
+	fsc->args[2] = regs.r_rdx;
+	fsc->args[3] = regs.r_rsi;
+	fsc->args[4] = regs.r_rdi;
 
-	sc = get_syscall(fsc.name);
+	sc = get_syscall(fsc->name);
 	if (sc)
-		fsc.nargs = sc->nargs;
+		fsc->nargs = sc->nargs;
 	else {
 #if DEBUG
 		fprintf(trussinfo->outfile, "unknown syscall %s -- setting "
-		    "args to %d\n", fsc.name, nargs);
+		    "args to %d\n", fsc->name, nargs);
 #endif
-		fsc.nargs = nargs;
+		fsc->nargs = nargs;
 	}
 
-	fsc.s_args = calloc(1, (1 + fsc.nargs) * sizeof(char *));
-	fsc.sc = sc;
+	fsc->s_args = calloc(1, (1 + fsc->nargs) * sizeof(char *));
+	fsc->sc = sc;
 
 	/*
 	 * At this point, we set up the system call arguments.
@@ -176,19 +183,19 @@ amd64_linux32_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	 * passed in *and* out, however.
 	 */
 
-	if (fsc.name) {
+	if (fsc->name) {
 #if DEBUG
-		fprintf(stderr, "syscall %s(", fsc.name);
+		fprintf(stderr, "syscall %s(", fsc->name);
 #endif
-		for (i = 0; i < fsc.nargs; i++) {
+		for (i = 0; i < fsc->nargs; i++) {
 #if DEBUG
 			fprintf(stderr, "0x%x%s", sc ?
-			    fsc.args[sc->args[i].offset] : fsc.args[i],
-			    i < (fsc.nargs - 1) ? "," : "");
+			    fsc->args[sc->args[i].offset] : fsc->args[i],
+			    i < (fsc->nargs - 1) ? "," : "");
 #endif
 			if (sc && !(sc->args[i].type & OUT)) {
-				fsc.s_args[i] = print_arg(&sc->args[i],
-				    fsc.args, 0, trussinfo);
+				fsc->s_args[i] = print_arg(&sc->args[i],
+				    fsc->args, 0, trussinfo);
 			}
 		}
 #if DEBUG
@@ -200,30 +207,29 @@ amd64_linux32_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	fprintf(trussinfo->outfile, "\n");
 #endif
 
-	if (fsc.name != NULL && (strcmp(fsc.name, "linux_execve") == 0 ||
-	    strcmp(fsc.name, "exit") == 0)) {
+	if (fsc->name != NULL && (strcmp(fsc->name, "linux_execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0)) {
 		/*
 		 * XXX
 		 * This could be done in a more general
 		 * manner but it still wouldn't be very pretty.
 		 */
-		if (strcmp(fsc.name, "linux_execve") == 0) {
+		if (strcmp(fsc->name, "linux_execve") == 0) {
 			if ((trussinfo->flags & EXECVEARGS) == 0) {
-				if (fsc.s_args[1]) {
-					free(fsc.s_args[1]);
-					fsc.s_args[1] = NULL;
+				if (fsc->s_args[1]) {
+					free(fsc->s_args[1]);
+					fsc->s_args[1] = NULL;
 				}
 			}
 			if ((trussinfo->flags & EXECVEENVS) == 0) {
-				if (fsc.s_args[2]) {
-					free(fsc.s_args[2]);
-					fsc.s_args[2] = NULL;
+				if (fsc->s_args[2]) {
+					free(fsc->s_args[2]);
+					fsc->s_args[2] = NULL;
 				}
 			}
 		}
 	}
-
-	return;
+	trussinfo->curthread->fsc = fsc;
 }
 
 /*
@@ -246,16 +252,18 @@ amd64_linux32_syscall_exit(struct trussinfo *trussinfo,
     int syscall_num __unused)
 {
 	struct reg regs;
+	struct linux_syscall *fsc;
 	struct syscall *sc;
+	lwpid_t tid;
 	long retval;
 	int errorp, i;
 
-	if (fsc.name == NULL)
+	if (trussinfo->curthread->fsc == NULL)
 		return (-1);
 
-	cpid = trussinfo->curthread->tid;
+	tid = trussinfo->curthread->tid;
 
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
 		return (-1);
 	}
@@ -268,10 +276,11 @@ amd64_linux32_syscall_exit(struct trussinfo *trussinfo,
 	 * stand some significant cleaning.
 	 */
 
-	sc = fsc.sc;
+	fsc = trussinfo->curthread->fsc;
+	sc = fsc->sc;
 	if (!sc) {
-		for (i = 0; i < fsc.nargs; i++)
-			asprintf(&fsc.s_args[i], "0x%lx", fsc.args[i]);
+		for (i = 0; i < fsc->nargs; i++)
+			asprintf(&fsc->s_args[i], "0x%lx", fsc->args[i]);
 	} else {
 		/*
 		 * Here, we only look for arguments that have OUT masked in --
@@ -286,12 +295,12 @@ amd64_linux32_syscall_exit(struct trussinfo *trussinfo,
 				 */
 				if (errorp) {
 					asprintf(&temp, "0x%lx",
-					    fsc.args[sc->args[i].offset]);
+					    fsc->args[sc->args[i].offset]);
 				} else {
 					temp = print_arg(&sc->args[i],
-					    fsc.args, retval, trussinfo);
+					    fsc->args, retval, trussinfo);
 				}
-				fsc.s_args[i] = temp;
+				fsc->s_args[i] = temp;
 			}
 		}
 	}
@@ -308,13 +317,13 @@ amd64_linux32_syscall_exit(struct trussinfo *trussinfo,
 		}
 	}
 
-	if (fsc.name != NULL && (strcmp(fsc.name, "linux_execve") == 0 ||
-	    strcmp(fsc.name, "exit") == 0))
+	if (fsc->name != NULL && (strcmp(fsc->name, "linux_execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0))
 		trussinfo->curthread->in_syscall = 1;
 
-	print_syscall_ret(trussinfo, fsc.name, fsc.nargs, fsc.s_args, errorp,
-	    errorp ? i : retval, fsc.sc);
-	clear_fsc();
+	print_syscall_ret(trussinfo, fsc->name, fsc->nargs, fsc->s_args, errorp,
+	    errorp ? i : retval, fsc->sc);
+	free_fsc(fsc);
 
 	return (retval);
 }
diff --git a/usr.bin/truss/i386-fbsd.c b/usr.bin/truss/i386-fbsd.c
index cbf2d1e..d146ecd 100644
--- a/usr.bin/truss/i386-fbsd.c
+++ b/usr.bin/truss/i386-fbsd.c
@@ -62,8 +62,6 @@ static const char rcsid[] =
 #include "syscall.h"
 #include "extern.h"
 
-static int cpid = -1;
-
 #include "syscalls.h"
 
 static int nsyscalls = sizeof(syscallnames) / sizeof(syscallnames[0]);
@@ -77,30 +75,35 @@ static int nsyscalls = sizeof(syscallnames) / sizeof(syscallnames[0]);
  * 'struct syscall' describes the system call; it may be NULL, however,
  * if we don't know about this particular system call yet.
  */
-static struct freebsd_syscall {
+struct freebsd_syscall {
 	struct syscall *sc;
 	const char *name;
 	int number;
 	unsigned long *args;
 	int nargs;	/* number of arguments -- *not* number of words! */
 	char **s_args;	/* the printable arguments */
-} fsc;
+};
+
+static struct freebsd_syscall *
+alloc_fsc(void)
+{
+
+	return (malloc(sizeof(struct freebsd_syscall)));
+}
 
 /* Clear up and free parts of the fsc structure. */
-static __inline void
-clear_fsc(void)
+static void
+free_fsc(struct freebsd_syscall *fsc)
 {
 	int i;
 
-	if (fsc.args)
-		free(fsc.args);
-	if (fsc.s_args) {
-		for (i = 0; i < fsc.nargs; i++)
-			if (fsc.s_args[i])
-				free(fsc.s_args[i]);
-		free(fsc.s_args);
+	free(fsc->args);
+	if (fsc->s_args) {
+		for (i = 0; i < fsc->nargs; i++)
+			free(fsc->s_args[i]);
+		free(fsc->s_args);
 	}
-	memset(&fsc, 0, sizeof(fsc));
+	free(fsc);
 }
 
 /*
@@ -115,15 +118,15 @@ i386_syscall_entry(struct trussinfo *trussinfo, int nargs)
 {
 	struct ptrace_io_desc iorequest;
 	struct reg regs;
+	struct freebsd_syscall *fsc;
 	struct syscall *sc;
+	lwpid_t tid;
 	unsigned int parm_offset;
 	int i, syscall_num;
 
-	clear_fsc();
-
-	cpid = trussinfo->curthread->tid;
+	tid = trussinfo->curthread->tid;
 
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
 		return;
 	}
@@ -137,56 +140,59 @@ i386_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	syscall_num = regs.r_eax;
 	switch (syscall_num) {
 	case SYS_syscall:
-		syscall_num = ptrace(PT_READ_D, cpid, (caddr_t)parm_offset, 0);
+		syscall_num = ptrace(PT_READ_D, tid, (caddr_t)parm_offset, 0);
 		parm_offset += sizeof(int);
 		break;
 	case SYS___syscall:
-		syscall_num = ptrace(PT_READ_D, cpid, (caddr_t)parm_offset, 0);
+		syscall_num = ptrace(PT_READ_D, tid, (caddr_t)parm_offset, 0);
 		parm_offset += sizeof(quad_t);
 		break;
 	}
 
-	fsc.number = syscall_num;
-	fsc.name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
+	fsc = alloc_fsc();
+	if (fsc == NULL)
+		return;
+	fsc->number = syscall_num;
+	fsc->name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
 	    NULL : syscallnames[syscall_num];
-	if (!fsc.name) {
+	if (!fsc->name) {
 		fprintf(trussinfo->outfile, "-- UNKNOWN SYSCALL %d --\n",
 		    syscall_num);
 	}
 
-	if (fsc.name && (trussinfo->flags & FOLLOWFORKS) &&
-	    (strcmp(fsc.name, "fork") == 0 ||
-	    strcmp(fsc.name, "rfork") == 0 ||
-	    strcmp(fsc.name, "vfork") == 0))
+	if (fsc->name && (trussinfo->flags & FOLLOWFORKS) &&
+	    (strcmp(fsc->name, "fork") == 0 ||
+	    strcmp(fsc->name, "rfork") == 0 ||
+	    strcmp(fsc->name, "vfork") == 0))
 		trussinfo->curthread->in_fork = 1;
 
 	if (nargs == 0)
 		return;
 
-	fsc.args = malloc((1 + nargs) * sizeof(unsigned long));
+	fsc->args = malloc((1 + nargs) * sizeof(unsigned long));
 	iorequest.piod_op = PIOD_READ_D;
 	iorequest.piod_offs = (void *)parm_offset;
-	iorequest.piod_addr = fsc.args;
+	iorequest.piod_addr = fsc->args;
 	iorequest.piod_len = (1 + nargs) * sizeof(unsigned long);
-	ptrace(PT_IO, cpid, (caddr_t)&iorequest, 0);
+	ptrace(PT_IO, tid, (caddr_t)&iorequest, 0);
 	if (iorequest.piod_len == 0)
 		return;
 
 	sc = NULL;
-	if (fsc.name)
-		sc = get_syscall(fsc.name);
+	if (fsc->name)
+		sc = get_syscall(fsc->name);
 	if (sc)
-		fsc.nargs = sc->nargs;
+		fsc->nargs = sc->nargs;
 	else {
 #if DEBUG
 		fprintf(trussinfo->outfile, "unknown syscall %s -- setting "
-		    "args to %d\n", fsc.name, nargs);
+		    "args to %d\n", fsc->name, nargs);
 #endif
-		fsc.nargs = nargs;
+		fsc->nargs = nargs;
 	}
 
-	fsc.s_args = calloc(1, (1 + fsc.nargs) * sizeof(char *));
-	fsc.sc = sc;
+	fsc->s_args = calloc(1, (1 + fsc->nargs) * sizeof(char *));
+	fsc->sc = sc;
 
 	/*
 	 * At this point, we set up the system call arguments.
@@ -196,19 +202,19 @@ i386_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	 * passed in *and* out, however.
 	 */
 
-	if (fsc.name) {
+	if (fsc->name) {
 #if DEBUG
-		fprintf(stderr, "syscall %s(", fsc.name);
+		fprintf(stderr, "syscall %s(", fsc->name);
 #endif
-		for (i = 0; i < fsc.nargs; i++) {
+		for (i = 0; i < fsc->nargs; i++) {
 #if DEBUG
 			fprintf(stderr, "0x%x%s", sc ?
-			    fsc.args[sc->args[i].offset] : fsc.args[i],
-			    i < (fsc.nargs - 1) ? "," : "");
+			    fsc->args[sc->args[i].offset] : fsc->args[i],
+			    i < (fsc->nargs - 1) ? "," : "");
 #endif
 			if (sc && !(sc->args[i].type & OUT)) {
-				fsc.s_args[i] = print_arg(&sc->args[i],
-				    fsc.args, 0, trussinfo);
+				fsc->s_args[i] = print_arg(&sc->args[i],
+				    fsc->args, 0, trussinfo);
 			}
 		}
 #if DEBUG
@@ -220,30 +226,29 @@ i386_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	fprintf(trussinfo->outfile, "\n");
 #endif
 
-	if (fsc.name != NULL && (strcmp(fsc.name, "execve") == 0 ||
-	    strcmp(fsc.name, "exit") == 0)) {
+	if (fsc->name != NULL && (strcmp(fsc->name, "execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0)) {
 		/*
 		 * XXX
 		 * This could be done in a more general
 		 * manner but it still wouldn't be very pretty.
 		 */
-		if (strcmp(fsc.name, "execve") == 0) {
+		if (strcmp(fsc->name, "execve") == 0) {
 			if ((trussinfo->flags & EXECVEARGS) == 0) {
-				if (fsc.s_args[1]) {
-					free(fsc.s_args[1]);
-					fsc.s_args[1] = NULL;
+				if (fsc->s_args[1]) {
+					free(fsc->s_args[1]);
+					fsc->s_args[1] = NULL;
 				}
 			}
 			if ((trussinfo->flags & EXECVEENVS) == 0) {
-				if (fsc.s_args[2]) {
-					free(fsc.s_args[2]);
-					fsc.s_args[2] = NULL;
+				if (fsc->s_args[2]) {
+					free(fsc->s_args[2]);
+					fsc->s_args[2] = NULL;
 				}
 			}
 		}
 	}
-
-	return;
+	trussinfo->curthread->fsc = fsc;
 }
 
 /*
@@ -257,16 +262,18 @@ long
 i386_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 {
 	struct reg regs;
+	struct freebsd_syscall *fsc;
 	struct syscall *sc;
+	lwpid_t tid;
 	long retval;
 	int errorp, i;
 
-	if (fsc.name == NULL)
+	if (trussinfo->curthread->fsc == NULL)
 		return (-1);
 
-	cpid = trussinfo->curthread->tid;
+	tid = trussinfo->curthread->tid;
 
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
 		return (-1);
 	}
@@ -279,10 +286,11 @@ i386_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 	 * stand some significant cleaning.
 	 */
 
-	sc = fsc.sc;
+	fsc = trussinfo->curthread->fsc;
+	sc = fsc->sc;
 	if (!sc) {
-		for (i = 0; i < fsc.nargs; i++)
-			asprintf(&fsc.s_args[i], "0x%lx", fsc.args[i]);
+		for (i = 0; i < fsc->nargs; i++)
+			asprintf(&fsc->s_args[i], "0x%lx", fsc->args[i]);
 	} else {
 		/*
 		 * Here, we only look for arguments that have OUT masked in --
@@ -297,18 +305,18 @@ i386_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 				 */
 				if (errorp) {
 					asprintf(&temp, "0x%lx",
-					    fsc.args[sc->args[i].offset]);
+					    fsc->args[sc->args[i].offset]);
 				} else {
 					temp = print_arg(&sc->args[i],
-					    fsc.args, retval, trussinfo);
+					    fsc->args, retval, trussinfo);
 				}
-				fsc.s_args[i] = temp;
+				fsc->s_args[i] = temp;
 			}
 		}
 	}
 
-	if (fsc.name != NULL && (strcmp(fsc.name, "execve") == 0 ||
-	    strcmp(fsc.name, "exit") == 0))
+	if (fsc->name != NULL && (strcmp(fsc->name, "execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0))
 		trussinfo->curthread->in_syscall = 1;
 
 	/*
@@ -316,9 +324,9 @@ i386_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 	 * but that complicates things considerably.
 	 */
 
-	print_syscall_ret(trussinfo, fsc.name, fsc.nargs, fsc.s_args, errorp,
-	    retval, fsc.sc);
-	clear_fsc();
+	print_syscall_ret(trussinfo, fsc->name, fsc->nargs, fsc->s_args, errorp,
+	    retval, fsc->sc);
+	free_fsc(fsc);
 
 	return (retval);
 }
diff --git a/usr.bin/truss/i386-linux.c b/usr.bin/truss/i386-linux.c
index 6a0c261..84f1451 100644
--- a/usr.bin/truss/i386-linux.c
+++ b/usr.bin/truss/i386-linux.c
@@ -59,8 +59,6 @@ static const char rcsid[] =
 #include "syscall.h"
 #include "extern.h"
 
-static int cpid = -1;
-
 #include "linux_syscalls.h"
 
 static int nsyscalls =
@@ -75,28 +73,34 @@ static int nsyscalls =
  * 'struct syscall' describes the system call; it may be NULL, however,
  * if we don't know about this particular system call yet.
  */
-static struct linux_syscall {
+struct linux_syscall {
 	struct syscall *sc;
 	const char *name;
 	int number;
 	unsigned long args[5];
 	int nargs;	/* number of arguments -- *not* number of words! */
 	char **s_args;	/* the printable arguments */
-} fsc;
+};
+
+static struct linux_syscall *
+alloc_fsc(void)
+{
+
+	return (malloc(sizeof(struct linux_syscall)));
+}
 
 /* Clear up and free parts of the fsc structure. */
-static __inline void
-clear_fsc(void)
+static void
+free_fsc(struct linux_syscall *fsc)
 {
 	int i;
 
-	if (fsc.s_args) {
-		for (i = 0; i < fsc.nargs; i++)
-			if (fsc.s_args[i])
-				free(fsc.s_args[i]);
-		free(fsc.s_args);
+	if (fsc->s_args) {
+		for (i = 0; i < fsc->nargs; i++)
+			free(fsc->s_args[i]);
+		free(fsc->s_args);
 	}
-	memset(&fsc, 0, sizeof(fsc));
+	free(fsc);
 }
 
 /*
@@ -110,31 +114,34 @@ void
 i386_linux_syscall_entry(struct trussinfo *trussinfo, int nargs)
 {
 	struct reg regs;
+	struct linux_syscall *fsc;
 	struct syscall *sc;
+	lwpid_t tid;
 	int i, syscall_num;
 
-	clear_fsc();
-
-	cpid = trussinfo->curthread->tid;
+	tid = trussinfo->curthread->tid;
 
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
 		return;
 	}
 
 	syscall_num = regs.r_eax;
 
-	fsc.number = syscall_num;
-	fsc.name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
+	fsc = alloc_fsc();
+	if (fsc == NULL)
+		return;
+	fsc->number = syscall_num;
+	fsc->name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
 	    NULL : linux_syscallnames[syscall_num];
-	if (!fsc.name) {
+	if (!fsc->name) {
 		fprintf(trussinfo->outfile, "-- UNKNOWN SYSCALL %d --\n",
 		    syscall_num);
 	}
 
-	if (fsc.name && (trussinfo->flags & FOLLOWFORKS) &&
-	    (strcmp(fsc.name, "linux_fork") == 0 ||
-	    strcmp(fsc.name, "linux_vfork") == 0))
+	if (fsc->name && (trussinfo->flags & FOLLOWFORKS) &&
+	    (strcmp(fsc->name, "linux_fork") == 0 ||
+	    strcmp(fsc->name, "linux_vfork") == 0))
 		trussinfo->curthread->in_fork = 1;
 
 	if (nargs == 0)
@@ -148,25 +155,25 @@ i386_linux_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	 * that have more than five arguments?
 	 */
 
-	fsc.args[0] = regs.r_ebx;
-	fsc.args[1] = regs.r_ecx;
-	fsc.args[2] = regs.r_edx;
-	fsc.args[3] = regs.r_esi;
-	fsc.args[4] = regs.r_edi;
+	fsc->args[0] = regs.r_ebx;
+	fsc->args[1] = regs.r_ecx;
+	fsc->args[2] = regs.r_edx;
+	fsc->args[3] = regs.r_esi;
+	fsc->args[4] = regs.r_edi;
 
-	sc = get_syscall(fsc.name);
+	sc = get_syscall(fsc->name);
 	if (sc)
-		fsc.nargs = sc->nargs;
+		fsc->nargs = sc->nargs;
 	else {
 #if DEBUG
 		fprintf(trussinfo->outfile, "unknown syscall %s -- setting "
-		    "args to %d\n", fsc.name, nargs);
+		    "args to %d\n", fsc->name, nargs);
 #endif
-		fsc.nargs = nargs;
+		fsc->nargs = nargs;
 	}
 
-	fsc.s_args = calloc(1, (1 + fsc.nargs) * sizeof(char *));
-	fsc.sc = sc;
+	fsc->s_args = calloc(1, (1 + fsc->nargs) * sizeof(char *));
+	fsc->sc = sc;
 
 	/*
 	 * At this point, we set up the system call arguments.
@@ -176,19 +183,19 @@ i386_linux_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	 * passed in *and* out, however.
 	 */
 
-	if (fsc.name) {
+	if (fsc->name) {
 #if DEBUG
-		fprintf(stderr, "syscall %s(", fsc.name);
+		fprintf(stderr, "syscall %s(", fsc->name);
 #endif
-		for (i = 0; i < fsc.nargs; i++) {
+		for (i = 0; i < fsc->nargs; i++) {
 #if DEBUG
 			fprintf(stderr, "0x%x%s", sc ?
-			    fsc.args[sc->args[i].offset] : fsc.args[i],
-			    i < (fsc.nargs - 1) ? "," : "");
+			    fsc->args[sc->args[i].offset] : fsc->args[i],
+			    i < (fsc->nargs - 1) ? "," : "");
 #endif
 			if (sc && !(sc->args[i].type & OUT)) {
-				fsc.s_args[i] = print_arg(&sc->args[i],
-				    fsc.args, 0, trussinfo);
+				fsc->s_args[i] = print_arg(&sc->args[i],
+				    fsc->args, 0, trussinfo);
 			}
 		}
 #if DEBUG
@@ -200,30 +207,29 @@ i386_linux_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	fprintf(trussinfo->outfile, "\n");
 #endif
 
-	if (fsc.name != NULL && (strcmp(fsc.name, "linux_execve") == 0 ||
-	    strcmp(fsc.name, "exit") == 0)) {
+	if (fsc->name != NULL && (strcmp(fsc->name, "linux_execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0)) {
 		/*
 		 * XXX
 		 * This could be done in a more general
 		 * manner but it still wouldn't be very pretty.
 		 */
-		if (strcmp(fsc.name, "linux_execve") == 0) {
+		if (strcmp(fsc->name, "linux_execve") == 0) {
 			if ((trussinfo->flags & EXECVEARGS) == 0) {
-				if (fsc.s_args[1]) {
-					free(fsc.s_args[1]);
-					fsc.s_args[1] = NULL;
+				if (fsc->s_args[1]) {
+					free(fsc->s_args[1]);
+					fsc->s_args[1] = NULL;
 				}
 			}
 			if ((trussinfo->flags & EXECVEENVS) == 0) {
-				if (fsc.s_args[2]) {
-					free(fsc.s_args[2]);
-					fsc.s_args[2] = NULL;
+				if (fsc->s_args[2]) {
+					free(fsc->s_args[2]);
+					fsc->s_args[2] = NULL;
 				}
 			}
 		}
 	}
-
-	return;
+	trussinfo->curthread->fsc = fsc;
 }
 
 /*
@@ -245,16 +251,18 @@ long
 i386_linux_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 {
 	struct reg regs;
+	struct linux_syscall *fsc;
 	struct syscall *sc;
+	lwpid_t tid;
 	long retval;
 	int errorp, i;
 
-	if (fsc.name == NULL)
+	if (trussinfo->curthread->fsc == NULL)
 		return (-1);
 
-	cpid = trussinfo->curthread->tid;
+	tid = trussinfo->curthread->tid;
 
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
 		return (-1);
 	}
@@ -267,10 +275,11 @@ i386_linux_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 	 * stand some significant cleaning.
 	 */
 
-	sc = fsc.sc;
+	fsc = trussinfo->curthread->fsc;
+	sc = fsc->sc;
 	if (!sc) {
-		for (i = 0; i < fsc.nargs; i++)
-			asprintf(&fsc.s_args[i], "0x%lx", fsc.args[i]);
+		for (i = 0; i < fsc->nargs; i++)
+			asprintf(&fsc->s_args[i], "0x%lx", fsc->args[i]);
 	} else {
 		/*
 		 * Here, we only look for arguments that have OUT masked in --
@@ -285,12 +294,12 @@ i386_linux_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 				 */
 				if (errorp) {
 					asprintf(&temp, "0x%lx",
-					    fsc.args[sc->args[i].offset]);
+					    fsc->args[sc->args[i].offset]);
 				} else {
 					temp = print_arg(&sc->args[i],
-					    fsc.args, retval, trussinfo);
+					    fsc->args, retval, trussinfo);
 				}
-				fsc.s_args[i] = temp;
+				fsc->s_args[i] = temp;
 			}
 		}
 	}
@@ -307,13 +316,13 @@ i386_linux_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 		}
 	}
 
-	if (fsc.name != NULL && (strcmp(fsc.name, "linux_execve") == 0 ||
-	    strcmp(fsc.name, "exit") == 0))
+	if (fsc->name != NULL && (strcmp(fsc->name, "linux_execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0))
 		trussinfo->curthread->in_syscall = 1;
 
-	print_syscall_ret(trussinfo, fsc.name, fsc.nargs, fsc.s_args, errorp,
-	    errorp ? i : retval, fsc.sc);
-	clear_fsc();
+	print_syscall_ret(trussinfo, fsc->name, fsc->nargs, fsc->s_args, errorp,
+	    errorp ? i : retval, fsc->sc);
+	free_fsc(fsc);
 
 	return (retval);
 }
diff --git a/usr.bin/truss/ia64-fbsd.c b/usr.bin/truss/ia64-fbsd.c
index 951917f..2218fe5 100644
--- a/usr.bin/truss/ia64-fbsd.c
+++ b/usr.bin/truss/ia64-fbsd.c
@@ -61,8 +61,6 @@ static const char rcsid[] =
 #include "syscall.h"
 #include "extern.h"
 
-static int cpid = -1;
-
 #include "syscalls.h"
 
 static int nsyscalls = sizeof(syscallnames) / sizeof(syscallnames[0]);
@@ -76,30 +74,35 @@ static int nsyscalls = sizeof(syscallnames) / sizeof(syscallnames[0]);
  * 'struct syscall' describes the system call; it may be NULL, however,
  * if we don't know about this particular system call yet.
  */
-static struct freebsd_syscall {
+struct freebsd_syscall {
 	struct syscall *sc;
 	const char *name;
 	int number;
 	unsigned long *args;
 	int nargs;	/* number of arguments -- *not* number of words! */
 	char **s_args;	/* the printable arguments */
-} fsc;
+};
+
+static struct freebsd_syscall *
+alloc_fsc(void)
+{
+
+	return (malloc(sizeof(struct freebsd_syscall)));
+}
 
 /* Clear up and free parts of the fsc structure. */
-static __inline void
-clear_fsc(void)
+static void
+free_fsc(struct freebsd_syscall *fsc)
 {
 	int i;
 
-	if (fsc.args)
-		free(fsc.args);
-	if (fsc.s_args) {
-		for (i = 0; i < fsc.nargs; i++)
-			if (fsc.s_args[i])
-				free(fsc.s_args[i]);
-		free(fsc.s_args);
+	free(fsc->args);
+	if (fsc->s_args) {
+		for (i = 0; i < fsc->nargs; i++)
+			free(fsc->s_args[i]);
+		free(fsc->s_args);
 	}
-	memset(&fsc, 0, sizeof(fsc));
+	free(fsc);
 }
 
 /*
@@ -113,15 +116,15 @@ void
 ia64_syscall_entry(struct trussinfo *trussinfo, int nargs)
 {
 	struct reg regs;
+	struct freebsd_syscall *fsc;
 	struct syscall *sc;
 	unsigned long *parm_offset;
+	lwpid_t tid;
 	int i, syscall_num;
 
-	clear_fsc();
+	tid = trussinfo->curthread->tid;
 
-	cpid = trussinfo->curthread->tid;
-
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
 		return;
 	}
@@ -136,39 +139,42 @@ ia64_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	if (syscall_num == SYS_syscall || syscall_num == SYS___syscall)
 		syscall_num = (int)*parm_offset++;
 
-	fsc.number = syscall_num;
-	fsc.name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
+	fsc = alloc_fsc();
+	if (fsc == NULL)
+		return;
+	fsc->number = syscall_num;
+	fsc->name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
 	    NULL : syscallnames[syscall_num];
-	if (!fsc.name) {
+	if (!fsc->name) {
 		fprintf(trussinfo->outfile, "-- UNKNOWN SYSCALL %d --\n",
 		    syscall_num);
 	}
 
-	if (fsc.name && (trussinfo->flags & FOLLOWFORKS) &&
-	    (strcmp(fsc.name, "fork") == 0 ||
-	    strcmp(fsc.name, "rfork") == 0 ||
-	    strcmp(fsc.name, "vfork") == 0))
+	if (fsc->name && (trussinfo->flags & FOLLOWFORKS) &&
+	    (strcmp(fsc->name, "fork") == 0 ||
+	    strcmp(fsc->name, "rfork") == 0 ||
+	    strcmp(fsc->name, "vfork") == 0))
 		trussinfo->curthread->in_fork = 1;
 
 	if (nargs == 0)
 		return;
 
-	fsc.args = malloc((1 + nargs) * sizeof(unsigned long));
-	memcpy(fsc.args, parm_offset, nargs * sizeof(long));
+	fsc->args = malloc((1 + nargs) * sizeof(unsigned long));
+	memcpy(fsc->args, parm_offset, nargs * sizeof(long));
 
-	sc = get_syscall(fsc.name);
+	sc = get_syscall(fsc->name);
 	if (sc)
-		fsc.nargs = sc->nargs;
+		fsc->nargs = sc->nargs;
 	else {
 #if DEBUG
 		fprintf(trussinfo->outfile, "unknown syscall %s -- setting "
-		    "args to %d\n", fsc.name, nargs);
+		    "args to %d\n", fsc->name, nargs);
 #endif
-		fsc.nargs = nargs;
+		fsc->nargs = nargs;
 	}
 
-	fsc.s_args = calloc(1, (1 + fsc.nargs) * sizeof(char *));
-	fsc.sc = sc;
+	fsc->s_args = calloc(1, (1 + fsc->nargs) * sizeof(char *));
+	fsc->sc = sc;
 
 	/*
 	 * At this point, we set up the system call arguments.
@@ -178,19 +184,19 @@ ia64_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	 * passed in *and* out, however.
 	 */
 
-	if (fsc.name) {
+	if (fsc->name) {
 #if DEBUG
-		fprintf(stderr, "syscall %s(", fsc.name);
+		fprintf(stderr, "syscall %s(", fsc->name);
 #endif
-		for (i = 0; i < fsc.nargs; i++) {
+		for (i = 0; i < fsc->nargs; i++) {
 #if DEBUG
 			fprintf(stderr, "0x%x%s", sc ?
-			    fsc.args[sc->args[i].offset] : fsc.args[i],
-			    i < (fsc.nargs - 1) ? "," : "");
+			    fsc->args[sc->args[i].offset] : fsc->args[i],
+			    i < (fsc->nargs - 1) ? "," : "");
 #endif
 			if (sc && !(sc->args[i].type & OUT)) {
-				fsc.s_args[i] = print_arg(&sc->args[i],
-				    fsc.args, 0, trussinfo);
+				fsc->s_args[i] = print_arg(&sc->args[i],
+				    fsc->args, 0, trussinfo);
 			}
 		}
 #if DEBUG
@@ -202,30 +208,29 @@ ia64_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	fprintf(trussinfo->outfile, "\n");
 #endif
 
-	if (fsc.name != NULL && (strcmp(fsc.name, "execve") == 0 ||
-	    strcmp(fsc.name, "exit") == 0)) {
+	if (fsc->name != NULL && (strcmp(fsc->name, "execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0)) {
 		/*
 		 * XXX
 		 * This could be done in a more general
 		 * manner but it still wouldn't be very pretty.
 		 */
-		if (strcmp(fsc.name, "execve") == 0) {
+		if (strcmp(fsc->name, "execve") == 0) {
 			if ((trussinfo->flags & EXECVEARGS) == 0) {
-				if (fsc.s_args[1]) {
-					free(fsc.s_args[1]);
-					fsc.s_args[1] = NULL;
+				if (fsc->s_args[1]) {
+					free(fsc->s_args[1]);
+					fsc->s_args[1] = NULL;
 				}
 			}
 			if ((trussinfo->flags & EXECVEENVS) == 0) {
-				if (fsc.s_args[2]) {
-					free(fsc.s_args[2]);
-					fsc.s_args[2] = NULL;
+				if (fsc->s_args[2]) {
+					free(fsc->s_args[2]);
+					fsc->s_args[2] = NULL;
 				}
 			}
 		}
 	}
-
-	return;
+	trussinfo->curthread->fsc = fsc;
 }
 
 /*
@@ -239,16 +244,18 @@ long
 ia64_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 {
 	struct reg regs;
+	struct freebsd_syscall *fsc;
 	struct syscall *sc;
+	lwpid_t tid;
 	long retval;
 	int errorp, i;
 
-	if (fsc.name == NULL)
+	if (trussinfo->curthread->fsc == NULL)
 		return (-1);
 
-	cpid = trussinfo->curthread->tid;
+	tid = trussinfo->curthread->tid;
 
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
 		return (-1);
 	}
@@ -261,10 +268,11 @@ ia64_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 	 * stand some significant cleaning.
 	 */
 
-	sc = fsc.sc;
+	fsc = trussinfo->curthread->fsc;
+	sc = fsc->sc;
 	if (!sc) {
-		for (i = 0; i < fsc.nargs; i++)
-			asprintf(&fsc.s_args[i], "0x%lx", fsc.args[i]);
+		for (i = 0; i < fsc->nargs; i++)
+			asprintf(&fsc->s_args[i], "0x%lx", fsc->args[i]);
 	} else {
 		/*
 		 * Here, we only look for arguments that have OUT masked in --
@@ -279,27 +287,28 @@ ia64_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 				 */
 				if (errorp) {
 					asprintf(&temp, "0x%lx",
-					    fsc.args[sc->args[i].offset]);
+					    fsc->args[sc->args[i].offset]);
 				} else {
 					temp = print_arg(&sc->args[i],
-					    fsc.args, retval, trussinfo);
+					    fsc->args, retval, trussinfo);
 				}
-				fsc.s_args[i] = temp;
+				fsc->s_args[i] = temp;
 			}
 		}
 	}
 
-	if (fsc.name != NULL && (strcmp(fsc.name, "execve") == 0 ||
-	    strcmp(fsc.name, "exit") == 0))
+	if (fsc->name != NULL && (strcmp(fsc->name, "execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0))
 		trussinfo->curthread->in_syscall = 1;
+
 	/*
 	 * It would probably be a good idea to merge the error handling,
 	 * but that complicates things considerably.
 	 */
 
-	print_syscall_ret(trussinfo, fsc.name, fsc.nargs, fsc.s_args, errorp,
-	    retval, fsc.sc);
-	clear_fsc();
+	print_syscall_ret(trussinfo, fsc->name, fsc->nargs, fsc->s_args, errorp,
+	    retval, fsc->sc);
+	free_fsc(fsc);
 
 	return (retval);
 }
diff --git a/usr.bin/truss/main.c b/usr.bin/truss/main.c
index cb97293..02c6930 100644
--- a/usr.bin/truss/main.c
+++ b/usr.bin/truss/main.c
@@ -163,6 +163,7 @@ strsig(int sig)
 int
 main(int ac, char **av)
 {
+	struct timespec timediff;
 	struct sigaction sa;
 	struct ex_types *funcs;
 	struct trussinfo *trussinfo;
@@ -170,7 +171,7 @@ main(int ac, char **av)
 	char *signame;
 	char **command;
 	pid_t childpid;
-	int c, i, initial_open, status;
+	int c, initial_open, status;
 
 	fname = NULL;
 	initial_open = 1;
@@ -286,18 +287,17 @@ START_TRACE:
 	clock_gettime(CLOCK_REALTIME, &trussinfo->start_time);
 
 	do {
-		struct timespec timediff;
 		waitevent(trussinfo);
 
-		switch (i = trussinfo->pr_why) {
+		switch (trussinfo->pr_why) {
 		case S_SCE:
 			funcs->enter_syscall(trussinfo, MAXARGS);
 			clock_gettime(CLOCK_REALTIME,
-			    &trussinfo->before);
+			    &trussinfo->curthread->before);
 			break;
 		case S_SCX:
 			clock_gettime(CLOCK_REALTIME,
-			    &trussinfo->after);
+			    &trussinfo->curthread->after);
 
 			if (trussinfo->curthread->in_fork &&
 			    (trussinfo->flags & FOLLOWFORKS)) {
@@ -326,15 +326,15 @@ START_TRACE:
 				fprintf(trussinfo->outfile, "%5d: ",
 				    trussinfo->pid);
 			if (trussinfo->flags & ABSOLUTETIMESTAMPS) {
-				timespecsubt(&trussinfo->after,
+				timespecsubt(&trussinfo->curthread->after,
 				    &trussinfo->start_time, &timediff);
 				fprintf(trussinfo->outfile, "%ld.%09ld ",
 				    (long)timediff.tv_sec,
 				    timediff.tv_nsec);
 			}
 			if (trussinfo->flags & RELATIVETIMESTAMPS) {
-				timespecsubt(&trussinfo->after,
-				    &trussinfo->before, &timediff);
+				timespecsubt(&trussinfo->curthread->after,
+				    &trussinfo->curthread->before, &timediff);
 				fprintf(trussinfo->outfile, "%ld.%09ld ",
 				    (long)timediff.tv_sec,
 				    timediff.tv_nsec);
@@ -352,15 +352,15 @@ START_TRACE:
 				fprintf(trussinfo->outfile, "%5d: ",
 				    trussinfo->pid);
 			if (trussinfo->flags & ABSOLUTETIMESTAMPS) {
-				timespecsubt(&trussinfo->after,
+				timespecsubt(&trussinfo->curthread->after,
 				    &trussinfo->start_time, &timediff);
 				fprintf(trussinfo->outfile, "%ld.%09ld ",
 				    (long)timediff.tv_sec,
 				    timediff.tv_nsec);
 			}
 			if (trussinfo->flags & RELATIVETIMESTAMPS) {
-				timespecsubt(&trussinfo->after,
-				    &trussinfo->before, &timediff);
+				timespecsubt(&trussinfo->curthread->after,
+				    &trussinfo->curthread->before, &timediff);
 				fprintf(trussinfo->outfile, "%ld.%09ld ",
 				    (long)timediff.tv_sec, timediff.tv_nsec);
 			}
diff --git a/usr.bin/truss/mips-fbsd.c b/usr.bin/truss/mips-fbsd.c
index b141f80..6f5be66 100644
--- a/usr.bin/truss/mips-fbsd.c
+++ b/usr.bin/truss/mips-fbsd.c
@@ -66,8 +66,6 @@ static const char rcsid[] =
 #include "syscall.h"
 #include "extern.h"
 
-static int cpid = -1;
-
 #include "syscalls.h"
 
 static int nsyscalls = sizeof(syscallnames) / sizeof(syscallnames[0]);
@@ -81,30 +79,35 @@ static int nsyscalls = sizeof(syscallnames) / sizeof(syscallnames[0]);
  * 'struct syscall' describes the system call; it may be NULL, however,
  * if we don't know about this particular system call yet.
  */
-static struct freebsd_syscall {
+struct freebsd_syscall {
 	struct syscall *sc;
 	const char *name;
 	int number;
 	unsigned long *args;
 	int nargs;	/* number of arguments -- *not* number of words! */
 	char **s_args;	/* the printable arguments */
-} fsc;
+};
+
+static struct freebsd_syscall *
+alloc_fsc(void)
+{
+
+	return (malloc(sizeof(struct freebsd_syscall)));
+}
 
 /* Clear up and free parts of the fsc structure. */
-static __inline void
-clear_fsc(void)
+static void
+free_fsc(struct freebsd_syscall *fsc)
 {
 	int i;
 
-	if (fsc.args)
-		free(fsc.args);
-	if (fsc.s_args) {
-		for (i = 0; i < fsc.nargs; i++)
-			if (fsc.s_args[i])
-				free(fsc.s_args[i]);
-		free(fsc.s_args);
+	free(fsc->args);
+	if (fsc->s_args) {
+		for (i = 0; i < fsc->nargs; i++)
+			free(fsc->s_args[i]);
+		free(fsc->s_args);
 	}
-	memset(&fsc, 0, sizeof(fsc));
+	free(fsc);
 }
 
 /*
@@ -119,15 +122,15 @@ mips_syscall_entry(struct trussinfo *trussinfo, int nargs)
 {
 	struct ptrace_io_desc iorequest;
 	struct reg regs;
+	struct freebsd_syscall *fsc;
 	struct syscall *sc;
+	lwpid_t tid;
 	int i, syscall_num;
 	int indir;	/* indirect system call */
 
-	clear_fsc();
-
-	cpid = trussinfo->curthread->tid;
+	tid = trussinfo->curthread->tid;
 
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
 		return;
 	}
@@ -139,30 +142,33 @@ mips_syscall_entry(struct trussinfo *trussinfo, int nargs)
 		syscall_num = regs.r_regs[A0];
 	}
 
-	fsc.number = syscall_num;
-	fsc.name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
+	fsc = alloc_fsc();
+	if (fsc == NULL)
+		return;
+	fsc->number = syscall_num;
+	fsc->name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
 	    NULL : syscallnames[syscall_num];
-	if (!fsc.name) {
+	if (!fsc->name) {
 		fprintf(trussinfo->outfile, "-- UNKNOWN SYSCALL %d --\n",
 		    syscall_num);
 	}
 
-	if (fsc.name && (trussinfo->flags & FOLLOWFORKS) &&
-	    (strcmp(fsc.name, "fork") == 0 ||
-	    strcmp(fsc.name, "rfork") == 0 ||
-	    strcmp(fsc.name, "vfork") == 0))
+	if (fsc->name && (trussinfo->flags & FOLLOWFORKS) &&
+	    (strcmp(fsc->name, "fork") == 0 ||
+	    strcmp(fsc->name, "rfork") == 0 ||
+	    strcmp(fsc->name, "vfork") == 0))
 		trussinfo->curthread->in_fork = 1;
 
 	if (nargs == 0)
 		return;
 
-	fsc.args = malloc((1 + nargs) * sizeof(unsigned long));
+	fsc->args = malloc((1 + nargs) * sizeof(unsigned long));
 #if 0 // XXX
 	iorequest.piod_op = PIOD_READ_D;
 	iorequest.piod_offs = (void *)parm_offset;
-	iorequest.piod_addr = fsc.args;
+	iorequest.piod_addr = fsc->args;
 	iorequest.piod_len = (1 + nargs) * sizeof(unsigned long);
-	ptrace(PT_IO, cpid, (caddr_t)&iorequest, 0);
+	ptrace(PT_IO, tid, (caddr_t)&iorequest, 0);
 	if (iorequest.piod_len == 0)
 		return;
 #else
@@ -192,35 +198,35 @@ mips_syscall_entry(struct trussinfo *trussinfo, int nargs)
 		iorequest.piod_op = PIOD_READ_D;
 		iorequest.piod_offs = (void *)(regs.r_regs[SP] +
 		    4 * sizeof(uint32_t));
-		iorequest.piod_addr = &fsc.args[4];
-		iorequest.piod_len = (nargs - 4) * sizeof(fsc.args[0]);
-		ptrace(PT_IO, cpid, (caddr_t)&iorequest, 0);
+		iorequest.piod_addr = &fsc->args[4];
+		iorequest.piod_len = (nargs - 4) * sizeof(fsc->args[0]);
+		ptrace(PT_IO, tid, (caddr_t)&iorequest, 0);
 		if (iorequest.piod_len == 0)
 			return;
-	case 4:	fsc.args[3] = regs.r_regs[A3];
-	case 3:	fsc.args[2] = regs.r_regs[A2];
-	case 2:	fsc.args[1] = regs.r_regs[A1];
-	case 1:	fsc.args[0] = regs.r_regs[A0];
+	case 4:	fsc->args[3] = regs.r_regs[A3];
+	case 3:	fsc->args[2] = regs.r_regs[A2];
+	case 2:	fsc->args[1] = regs.r_regs[A1];
+	case 1:	fsc->args[0] = regs.r_regs[A0];
 	case 0: break;
 	}
 	if (indir) {
-		memmove(&fsc.args[0], &fsc.args[1],
-		    (nargs - 1) * sizeof(fsc.args[0]));
+		memmove(&fsc->args[0], &fsc->args[1],
+		    (nargs - 1) * sizeof(fsc->args[0]));
 	}
 
-	sc = get_syscall(fsc.name);
+	sc = get_syscall(fsc->name);
 	if (sc)
-		fsc.nargs = sc->nargs;
+		fsc->nargs = sc->nargs;
 	else {
 #if DEBUG
 		fprintf(trussinfo->outfile, "unknown syscall %s -- setting "
-		    "args to %d\n", fsc.name, nargs);
+		    "args to %d\n", fsc->name, nargs);
 #endif
-		fsc.nargs = nargs;
+		fsc->nargs = nargs;
 	}
 
-	fsc.s_args = calloc(1, (1 + fsc.nargs) * sizeof(char *));
-	fsc.sc = sc;
+	fsc->s_args = calloc(1, (1 + fsc->nargs) * sizeof(char *));
+	fsc->sc = sc;
 
 	/*
 	 * At this point, we set up the system call arguments.
@@ -230,19 +236,19 @@ mips_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	 * passed in *and* out, however.
 	 */
 
-	if (fsc.name) {
+	if (fsc->name) {
 #if DEBUG
-		fprintf(stderr, "syscall %s(", fsc.name);
+		fprintf(stderr, "syscall %s(", fsc->name);
 #endif
-		for (i = 0; i < fsc.nargs; i++) {
+		for (i = 0; i < fsc->nargs; i++) {
 #if DEBUG
 			fprintf(stderr, "0x%x%s", sc ?
-			    fsc.args[sc->args[i].offset] : fsc.args[i],
-			    i < (fsc.nargs - 1) ? "," : "");
+			    fsc->args[sc->args[i].offset] : fsc->args[i],
+			    i < (fsc->nargs - 1) ? "," : "");
 #endif
 			if (sc && !(sc->args[i].type & OUT)) {
-				fsc.s_args[i] = print_arg(&sc->args[i],
-				    fsc.args, 0, trussinfo);
+				fsc->s_args[i] = print_arg(&sc->args[i],
+				    fsc->args, 0, trussinfo);
 			}
 		}
 #if DEBUG
@@ -254,30 +260,29 @@ mips_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	fprintf(trussinfo->outfile, "\n");
 #endif
 
-	if (fsc.name != NULL && (strcmp(fsc.name, "execve") == 0 ||
-	    strcmp(fsc.name, "exit") == 0)) {
+	if (fsc->name != NULL && (strcmp(fsc->name, "execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0)) {
 		/*
 		 * XXX
 		 * This could be done in a more general
 		 * manner but it still wouldn't be very pretty.
 		 */
-		if (strcmp(fsc.name, "execve") == 0) {
+		if (strcmp(fsc->name, "execve") == 0) {
 			if ((trussinfo->flags & EXECVEARGS) == 0) {
-				if (fsc.s_args[1]) {
-					free(fsc.s_args[1]);
-					fsc.s_args[1] = NULL;
+				if (fsc->s_args[1]) {
+					free(fsc->s_args[1]);
+					fsc->s_args[1] = NULL;
 				}
 			}
 			if ((trussinfo->flags & EXECVEENVS) == 0) {
-				if (fsc.s_args[2]) {
-					free(fsc.s_args[2]);
-					fsc.s_args[2] = NULL;
+				if (fsc->s_args[2]) {
+					free(fsc->s_args[2]);
+					fsc->s_args[2] = NULL;
 				}
 			}
 		}
 	}
-
-	return;
+	trussinfo->curthread->fsc = fsc;
 }
 
 /*
@@ -291,16 +296,18 @@ long
 mips_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 {
 	struct reg regs;
+	struct freebsd_syscall *fsc;
 	struct syscall *sc;
+	lwpid_t tid;
 	long retval;
 	int errorp, i;
 
-	if (fsc.name == NULL)
+	if (trussinfo->curthread->fsc == NULL)
 		return (-1);
 
-	cpid = trussinfo->curthread->tid;
+	tid = trussinfo->curthread->tid;
 
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "\n");
 		return (-1);
 	}
@@ -313,10 +320,11 @@ mips_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 	 * stand some significant cleaning.
 	 */
 
-	sc = fsc.sc;
+	fsc = trussinfo->curthread->fsc;
+	sc = fsc->sc;
 	if (!sc) {
-		for (i = 0; i < fsc.nargs; i++)
-			asprintf(&fsc.s_args[i], "0x%lx", fsc.args[i]);
+		for (i = 0; i < fsc->nargs; i++)
+			asprintf(&fsc->s_args[i], "0x%lx", fsc->args[i]);
 	} else {
 		/*
 		 * Here, we only look for arguments that have OUT masked in --
@@ -331,18 +339,18 @@ mips_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 				 */
 				if (errorp) {
 					asprintf(&temp, "0x%lx",
-					    fsc.args[sc->args[i].offset]);
+					    fsc->args[sc->args[i].offset]);
 				} else {
 					temp = print_arg(&sc->args[i],
-					    fsc.args, retval, trussinfo);
+					    fsc->args, retval, trussinfo);
 				}
-				fsc.s_args[i] = temp;
+				fsc->s_args[i] = temp;
 			}
 		}
 	}
 
-	if (fsc.name != NULL && (strcmp(fsc.name, "execve") == 0 ||
-	    strcmp(fsc.name, "exit") == 0))
+	if (fsc->name != NULL && (strcmp(fsc->name, "execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0))
 		trussinfo->curthread->in_syscall = 1;
 
 	/*
@@ -350,9 +358,9 @@ mips_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 	 * but that complicates things considerably.
 	 */
 
-	print_syscall_ret(trussinfo, fsc.name, fsc.nargs, fsc.s_args, errorp,
-	    retval, fsc.sc);
-	clear_fsc();
+	print_syscall_ret(trussinfo, fsc->name, fsc->nargs, fsc->s_args, errorp,
+	    retval, fsc->sc);
+	free_fsc(fsc);
 
 	return (retval);
 }
diff --git a/usr.bin/truss/powerpc-fbsd.c b/usr.bin/truss/powerpc-fbsd.c
index e98b7ed..8cfb9ef 100644
--- a/usr.bin/truss/powerpc-fbsd.c
+++ b/usr.bin/truss/powerpc-fbsd.c
@@ -61,8 +61,6 @@ static const char rcsid[] =
 #include "syscall.h"
 #include "extern.h"
 
-static int cpid = -1;
-
 #ifdef __powerpc64__	/* 32-bit compatibility */
 #include "freebsd32_syscalls.h"
 #define	syscallnames	freebsd32_syscallnames
@@ -81,30 +79,35 @@ static int nsyscalls = sizeof(syscallnames) / sizeof(syscallnames[0]);
  * 'struct syscall' describes the system call; it may be NULL, however,
  * if we don't know about this particular system call yet.
  */
-static struct freebsd_syscall {
+struct freebsd_syscall {
 	struct syscall *sc;
 	const char *name;
 	int number;
 	unsigned long *args;
 	int nargs;	/* number of arguments -- *not* number of words! */
 	char **s_args;	/* the printable arguments */
-} fsc;
+};
+
+static struct freebsd_syscall *
+alloc_fsc(void)
+{
+
+	return (malloc(sizeof(struct freebsd_syscall)));
+}
 
 /* Clear up and free parts of the fsc structure. */
-static __inline void
-clear_fsc(void)
+static void
+free_fsc(struct freebsd_syscall *fsc)
 {
 	int i;
 
-	if (fsc.args)
-		free(fsc.args);
-	if (fsc.s_args) {
-		for (i = 0; i < fsc.nargs; i++)
-			if (fsc.s_args[i])
-				free(fsc.s_args[i]);
-		free(fsc.s_args);
+	free(fsc->args);
+	if (fsc->s_args) {
+		for (i = 0; i < fsc->nargs; i++)
+			free(fsc->s_args[i]);
+		free(fsc->s_args);
 	}
-	memset(&fsc, 0, sizeof(fsc));
+	free(fsc);
 }
 
 /*
@@ -119,18 +122,18 @@ powerpc_syscall_entry(struct trussinfo *trussinfo, int nargs)
 {
 	struct ptrace_io_desc iorequest;
 	struct reg regs;
+	struct freebsd_syscall *fsc;
 	struct syscall *sc;
 	void *args;
+	lwpid_t tid;
 	int i, regargs, syscall_num;
 
 	/* Account for a 64-bit argument with corresponding alignment. */
 	nargs += 2;
 
-	clear_fsc();
-
-	cpid = trussinfo->curthread->tid;
+	tid = trussinfo->curthread->tid;
 
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
 		return;
 	}
@@ -153,51 +156,54 @@ powerpc_syscall_entry(struct trussinfo *trussinfo, int nargs)
 		syscall_num = regs.fixreg[4];
 	}
 
-	fsc.number = syscall_num;
-	fsc.name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
+	fsc = alloc_fsc();
+	if (fsc == NULL)
+		return;
+	fsc->number = syscall_num;
+	fsc->name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
 	    NULL : syscallnames[syscall_num];
-	if (!fsc.name) {
+	if (!fsc->name) {
 		fprintf(trussinfo->outfile, "-- UNKNOWN SYSCALL %d --\n",
 		    syscall_num);
 	}
 
-	if (fsc.name && (trussinfo->flags & FOLLOWFORKS) &&
-	    (strcmp(fsc.name, "fork") == 0 ||
-	    strcmp(fsc.name, "rfork") == 0 ||
-	    strcmp(fsc.name, "vfork") == 0))
+	if (fsc->name && (trussinfo->flags & FOLLOWFORKS) &&
+	    (strcmp(fsc->name, "fork") == 0 ||
+	    strcmp(fsc->name, "rfork") == 0 ||
+	    strcmp(fsc->name, "vfork") == 0))
 		trussinfo->curthread->in_fork = 1;
 
 	if (nargs == 0)
 		return;
 
-	fsc.args = malloc((1 + nargs) * sizeof(unsigned long));
+	fsc->args = malloc((1 + nargs) * sizeof(unsigned long));
 
 	if (nargs > regargs) {
-		memmove(&fsc.args[0], args, regargs * sizeof(fsc.args[0]));
+		memmove(&fsc->args[0], args, regargs * sizeof(fsc->args[0]));
 
 		iorequest.piod_op = PIOD_READ_D;
 		iorequest.piod_offs = (void *)(regs.fixreg[1] + 8);
-		iorequest.piod_addr = &fsc.args[regargs];
-		iorequest.piod_len = (nargs - regargs) * sizeof(fsc.args[0]);
-		ptrace(PT_IO, cpid, (caddr_t)&iorequest, 0);
+		iorequest.piod_addr = &fsc->args[regargs];
+		iorequest.piod_len = (nargs - regargs) * sizeof(fsc->args[0]);
+		ptrace(PT_IO, tid, (caddr_t)&iorequest, 0);
 		if (iorequest.piod_len == 0)
 			return;
 	} else
-		memmove(&fsc.args[0], args, nargs * sizeof(fsc.args[0]));
+		memmove(&fsc->args[0], args, nargs * sizeof(fsc->args[0]));
 
-	sc = get_syscall(fsc.name);
+	sc = get_syscall(fsc->name);
 	if (sc)
-		fsc.nargs = sc->nargs;
+		fsc->nargs = sc->nargs;
 	else {
 #if DEBUG
 		fprintf(trussinfo->outfile, "unknown syscall %s -- setting "
-		    "args to %d\n", fsc.name, nargs);
+		    "args to %d\n", fsc->name, nargs);
 #endif
-		fsc.nargs = nargs;
+		fsc->nargs = nargs;
 	}
 
-	fsc.s_args = calloc(1, (1 + fsc.nargs) * sizeof(char *));
-	fsc.sc = sc;
+	fsc->s_args = calloc(1, (1 + fsc->nargs) * sizeof(char *));
+	fsc->sc = sc;
 
 	/*
 	 * At this point, we set up the system call arguments.
@@ -207,19 +213,19 @@ powerpc_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	 * passed in *and* out, however.
 	 */
 
-	if (fsc.name) {
+	if (fsc->name) {
 #if DEBUG
-		fprintf(stderr, "syscall %s(", fsc.name);
+		fprintf(stderr, "syscall %s(", fsc->name);
 #endif
-		for (i = 0; i < fsc.nargs; i++) {
+		for (i = 0; i < fsc->nargs; i++) {
 #if DEBUG
 			fprintf(stderr, "0x%x%s", sc ?
-			    fsc.args[sc->args[i].offset] : fsc.args[i],
-			    i < (fsc.nargs - 1) ? "," : "");
+			    fsc->args[sc->args[i].offset] : fsc->args[i],
+			    i < (fsc->nargs - 1) ? "," : "");
 #endif
 			if (sc && !(sc->args[i].type & OUT)) {
-				fsc.s_args[i] = print_arg(&sc->args[i],
-				    fsc.args, 0, trussinfo);
+				fsc->s_args[i] = print_arg(&sc->args[i],
+				    fsc->args, 0, trussinfo);
 			}
 		}
 #if DEBUG
@@ -231,30 +237,29 @@ powerpc_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	fprintf(trussinfo->outfile, "\n");
 #endif
 
-	if (fsc.name && (strcmp(fsc.name, "execve") == 0 ||
-	    strcmp(fsc.name, "exit") == 0)) {
+	if (fsc->name != NULL && (strcmp(fsc->name, "execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0)) {
 		/*
 		 * XXX
 		 * This could be done in a more general
 		 * manner but it still wouldn't be very pretty.
 		 */
-		if (strcmp(fsc.name, "execve") == 0) {
+		if (strcmp(fsc->name, "execve") == 0) {
 			if ((trussinfo->flags & EXECVEARGS) == 0) {
-				if (fsc.s_args[1]) {
-					free(fsc.s_args[1]);
-					fsc.s_args[1] = NULL;
+				if (fsc->s_args[1]) {
+					free(fsc->s_args[1]);
+					fsc->s_args[1] = NULL;
 				}
 			}
 			if ((trussinfo->flags & EXECVEENVS) == 0) {
-				if (fsc.s_args[2]) {
-					free(fsc.s_args[2]);
-					fsc.s_args[2] = NULL;
+				if (fsc->s_args[2]) {
+					free(fsc->s_args[2]);
+					fsc->s_args[2] = NULL;
 				}
 			}
 		}
 	}
-
-	return;
+	trussinfo->curthread->fsc = fsc;
 }
 
 /*
@@ -268,16 +273,18 @@ long
 powerpc_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 {
 	struct reg regs;
+	struct freebsd_syscall *fsc;
 	struct syscall *sc;
+	lwpid_t tid;
 	long retval;
 	int errorp, i;
 
-	if (fsc.name == NULL)
+	if (trussinfo->curthread->fsc == NULL)
 		return (-1);
 
-	cpid = trussinfo->curthread->tid;
+	tid = trussinfo->curthread->tid;
 
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "\n");
 		return (-1);
 	}
@@ -290,10 +297,11 @@ powerpc_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 	 * stand some significant cleaning.
 	 */
 
-	sc = fsc.sc;
+	fsc = trussinfo->curthread->fsc;
+	sc = fsc->sc;
 	if (!sc) {
-		for (i = 0; i < fsc.nargs; i++)
-			asprintf(&fsc.s_args[i], "0x%lx", fsc.args[i]);
+		for (i = 0; i < fsc->nargs; i++)
+			asprintf(&fsc->s_args[i], "0x%lx", fsc->args[i]);
 	} else {
 		/*
 		 * On 32-bit big-endian, the low word of a 64-bit return is
@@ -316,18 +324,18 @@ powerpc_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 				 */
 				if (errorp) {
 					asprintf(&temp, "0x%lx",
-					    fsc.args[sc->args[i].offset]);
+					    fsc->args[sc->args[i].offset]);
 				} else {
 					temp = print_arg(&sc->args[i],
-					    fsc.args, retval, trussinfo);
+					    fsc->args, retval, trussinfo);
 				}
-				fsc.s_args[i] = temp;
+				fsc->s_args[i] = temp;
 			}
 		}
 	}
 
-	if (fsc.name != NULL && (strcmp(fsc.name, "execve") == 0 ||
-	    strcmp(fsc.name, "exit") == 0))
+	if (fsc->name != NULL && (strcmp(fsc->name, "execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0))
 		trussinfo->curthread->in_syscall = 1;
 
 	/*
@@ -335,9 +343,9 @@ powerpc_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 	 * but that complicates things considerably.
 	 */
 
-	print_syscall_ret(trussinfo, fsc.name, fsc.nargs, fsc.s_args, errorp,
-	    retval, fsc.sc);
-	clear_fsc();
+	print_syscall_ret(trussinfo, fsc->name, fsc->nargs, fsc->s_args, errorp,
+	    retval, fsc->sc);
+	free_fsc(fsc);
 
 	return (retval);
 }
diff --git a/usr.bin/truss/powerpc64-fbsd.c b/usr.bin/truss/powerpc64-fbsd.c
index 0eae03f..7147f81 100644
--- a/usr.bin/truss/powerpc64-fbsd.c
+++ b/usr.bin/truss/powerpc64-fbsd.c
@@ -61,8 +61,6 @@ static const char rcsid[] =
 #include "syscall.h"
 #include "extern.h"
 
-static int cpid = -1;
-
 #include "syscalls.h"
 
 static int nsyscalls = sizeof(syscallnames) / sizeof(syscallnames[0]);
@@ -76,30 +74,35 @@ static int nsyscalls = sizeof(syscallnames) / sizeof(syscallnames[0]);
  * 'struct syscall' describes the system call; it may be NULL, however,
  * if we don't know about this particular system call yet.
  */
-static struct freebsd_syscall {
+struct freebsd_syscall {
 	struct syscall *sc;
 	const char *name;
 	int number;
 	unsigned long *args;
 	int nargs;	/* number of arguments -- *not* number of words! */
 	char **s_args;	/* the printable arguments */
-} fsc;
+};
+
+static struct freebsd_syscall *
+alloc_fsc(void)
+{
+
+	return (malloc(sizeof(struct freebsd_syscall)));
+}
 
 /* Clear up and free parts of the fsc structure. */
-static __inline void
-clear_fsc(void)
+static void
+free_fsc(struct freebsd_syscall *fsc)
 {
 	int i;
 
-	if (fsc.args)
-		free(fsc.args);
-	if (fsc.s_args) {
-		for (i = 0; i < fsc.nargs; i++)
-			if (fsc.s_args[i])
-				free(fsc.s_args[i]);
-		free(fsc.s_args);
+	free(fsc->args);
+	if (fsc->s_args) {
+		for (i = 0; i < fsc->nargs; i++)
+			free(fsc->s_args[i]);
+		free(fsc->s_args);
 	}
-	memset(&fsc, 0, sizeof(fsc));
+	free(fsc);
 }
 
 /*
@@ -114,15 +117,15 @@ powerpc64_syscall_entry(struct trussinfo *trussinfo, int nargs)
 {
 	struct ptrace_io_desc iorequest;
 	struct reg regs;
+	struct freebsd_syscall *fsc;
 	struct syscall *sc;
 	void *args;
+	lwpid_t tid;
 	int i, regargs, syscall_num;
 
-	clear_fsc();
-
-	cpid = trussinfo->curthread->tid;
+	tid = trussinfo->curthread->tid;
 
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
 		return;
 	}
@@ -141,51 +144,54 @@ powerpc64_syscall_entry(struct trussinfo *trussinfo, int nargs)
 		syscall_num = regs.fixreg[3];
 	}
 
-	fsc.number = syscall_num;
-	fsc.name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
+	fsc = alloc_fsc();
+	if (fsc == NULL)
+		return;
+	fsc->number = syscall_num;
+	fsc->name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
 	    NULL : syscallnames[syscall_num];
-	if (!fsc.name) {
+	if (!fsc->name) {
 		fprintf(trussinfo->outfile, "-- UNKNOWN SYSCALL %d --\n",
 		    syscall_num);
 	}
 
-	if (fsc.name && (trussinfo->flags & FOLLOWFORKS) &&
-	    (strcmp(fsc.name, "fork") == 0 ||
-	    strcmp(fsc.name, "rfork") == 0 ||
-	    strcmp(fsc.name, "vfork") == 0))
+	if (fsc->name && (trussinfo->flags & FOLLOWFORKS) &&
+	    (strcmp(fsc->name, "fork") == 0 ||
+	    strcmp(fsc->name, "rfork") == 0 ||
+	    strcmp(fsc->name, "vfork") == 0))
 		trussinfo->curthread->in_fork = 1;
 
 	if (nargs == 0)
 		return;
 
-	fsc.args = malloc((1 + nargs) * sizeof(unsigned long));
+	fsc->args = malloc((1 + nargs) * sizeof(unsigned long));
 
 	if (nargs > regargs) {
-		memmove(&fsc.args[0], args, regargs * sizeof(fsc.args[0]));
+		memmove(&fsc->args[0], args, regargs * sizeof(fsc->args[0]));
 
 		iorequest.piod_op = PIOD_READ_D;
 		iorequest.piod_offs = (void *)(regs.fixreg[1] + 48);
-		iorequest.piod_addr = &fsc.args[regargs];
-		iorequest.piod_len = (nargs - regargs) * sizeof(fsc.args[0]);
-		ptrace(PT_IO, cpid, (caddr_t)&iorequest, 0);
+		iorequest.piod_addr = &fsc->args[regargs];
+		iorequest.piod_len = (nargs - regargs) * sizeof(fsc->args[0]);
+		ptrace(PT_IO, tid, (caddr_t)&iorequest, 0);
 		if (iorequest.piod_len == 0)
 			return;
 	} else
-		memmove(&fsc.args[0], args, nargs * sizeof(fsc.args[0]));
+		memmove(&fsc->args[0], args, nargs * sizeof(fsc->args[0]));
 
-	sc = get_syscall(fsc.name);
+	sc = get_syscall(fsc->name);
 	if (sc)
-		fsc.nargs = sc->nargs;
+		fsc->nargs = sc->nargs;
 	else {
 #if DEBUG
 		fprintf(trussinfo->outfile, "unknown syscall %s -- setting "
-		    "args to %d\n", fsc.name, nargs);
+		    "args to %d\n", fsc->name, nargs);
 #endif
-		fsc.nargs = nargs;
+		fsc->nargs = nargs;
 	}
 
-	fsc.s_args = calloc(1, (1 + fsc.nargs) * sizeof(char *));
-	fsc.sc = sc;
+	fsc->s_args = calloc(1, (1 + fsc->nargs) * sizeof(char *));
+	fsc->sc = sc;
 
 	/*
 	 * At this point, we set up the system call arguments.
@@ -195,19 +201,19 @@ powerpc64_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	 * passed in *and* out, however.
 	 */
 
-	if (fsc.name) {
+	if (fsc->name) {
 #if DEBUG
-		fprintf(stderr, "syscall %s(", fsc.name);
+		fprintf(stderr, "syscall %s(", fsc->name);
 #endif
-		for (i = 0; i < fsc.nargs; i++) {
+		for (i = 0; i < fsc->nargs; i++) {
 #if DEBUG
 			fprintf(stderr, "0x%x%s", sc ?
-			    fsc.args[sc->args[i].offset] : fsc.args[i],
-			    i < (fsc.nargs - 1) ? "," : "");
+			    fsc->args[sc->args[i].offset] : fsc->args[i],
+			    i < (fsc->nargs - 1) ? "," : "");
 #endif
 			if (sc && !(sc->args[i].type & OUT)) {
-				fsc.s_args[i] = print_arg(&sc->args[i],
-				    fsc.args, 0, trussinfo);
+				fsc->s_args[i] = print_arg(&sc->args[i],
+				    fsc->args, 0, trussinfo);
 			}
 		}
 #if DEBUG
@@ -219,30 +225,29 @@ powerpc64_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	fprintf(trussinfo->outfile, "\n");
 #endif
 
-	if (fsc.name && (strcmp(fsc.name, "execve") == 0 ||
-	    strcmp(fsc.name, "exit") == 0)) {
+	if (fsc->name && (strcmp(fsc->name, "execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0)) {
 		/*
 		 * XXX
 		 * This could be done in a more general
 		 * manner but it still wouldn't be very pretty.
 		 */
-		if (strcmp(fsc.name, "execve") == 0) {
+		if (strcmp(fsc->name, "execve") == 0) {
 			if ((trussinfo->flags & EXECVEARGS) == 0) {
-				if (fsc.s_args[1]) {
-					free(fsc.s_args[1]);
-					fsc.s_args[1] = NULL;
+				if (fsc->s_args[1]) {
+					free(fsc->s_args[1]);
+					fsc->s_args[1] = NULL;
 				}
 			}
 			if ((trussinfo->flags & EXECVEENVS) == 0) {
-				if (fsc.s_args[2]) {
-					free(fsc.s_args[2]);
-					fsc.s_args[2] = NULL;
+				if (fsc->s_args[2]) {
+					free(fsc->s_args[2]);
+					fsc->s_args[2] = NULL;
 				}
 			}
 		}
 	}
-
-	return;
+	trussinfo->curthread->fsc = fsc;
 }
 
 /*
@@ -256,16 +261,18 @@ long
 powerpc64_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 {
 	struct reg regs;
+	struct freebsd_syscall *fsc;
 	struct syscall *sc;
+	lwpid_t tid;
 	long retval;
 	int errorp, i;
 
-	if (fsc.name == NULL)
+	if (trussinfo->curthread->fsc == NULL)
 		return (-1);
 
-	cpid = trussinfo->curthread->tid;
+	tid = trussinfo->curthread->tid;
 
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "\n");
 		return (-1);
 	}
@@ -278,10 +285,11 @@ powerpc64_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 	 * stand some significant cleaning.
 	 */
 
-	sc = fsc.sc;
+	fsc = trussinfo->curthread->fsc;
+	sc = fsc->sc;
 	if (!sc) {
-		for (i = 0; i < fsc.nargs; i++)
-			asprintf(&fsc.s_args[i], "0x%lx", fsc.args[i]);
+		for (i = 0; i < fsc->nargs; i++)
+			asprintf(&fsc->s_args[i], "0x%lx", fsc->args[i]);
 	} else {
 		/*
 		 * Here, we only look for arguments that have OUT masked in --
@@ -296,18 +304,18 @@ powerpc64_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 				 */
 				if (errorp) {
 					asprintf(&temp, "0x%lx",
-					    fsc.args[sc->args[i].offset]);
+					    fsc->args[sc->args[i].offset]);
 				} else {
 					temp = print_arg(&sc->args[i],
-					    fsc.args, retval, trussinfo);
+					    fsc->args, retval, trussinfo);
 				}
-				fsc.s_args[i] = temp;
+				fsc->s_args[i] = temp;
 			}
 		}
 	}
 
-	if (fsc.name != NULL && (strcmp(fsc.name, "execve") == 0 ||
-	    strcmp(fsc.name, "exit") == 0))
+	if (fsc->name != NULL && (strcmp(fsc->name, "execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0))
 		trussinfo->curthread->in_syscall = 1;
 
 	/*
@@ -315,9 +323,9 @@ powerpc64_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 	 * but that complicates things considerably.
 	 */
 
-	print_syscall_ret(trussinfo, fsc.name, fsc.nargs, fsc.s_args, errorp,
-	    retval, fsc.sc);
-	clear_fsc();
+	print_syscall_ret(trussinfo, fsc->name, fsc->nargs, fsc->s_args, errorp,
+	    retval, fsc->sc);
+	free_fsc(fsc);
 
 	return (retval);
 }
diff --git a/usr.bin/truss/setup.c b/usr.bin/truss/setup.c
index c855c33..d6e4300 100644
--- a/usr.bin/truss/setup.c
+++ b/usr.bin/truss/setup.c
@@ -161,12 +161,10 @@ find_thread(struct trussinfo *info, lwpid_t lwpid)
 		}
 	}
 
-	np = (struct threadinfo *)malloc(sizeof(struct threadinfo));
+	np = (struct threadinfo *)calloc(1, sizeof(struct threadinfo));
 	if (np == NULL)
-		errx(1, "malloc() failed");
+		err(1, "calloc() failed");
 	np->tid = lwpid;
-	np->in_fork = 0;
-	np->in_syscall = 0;
 	SLIST_INSERT_HEAD(&info->threadlist, np, entries);
 	info->curthread = np;
 }
diff --git a/usr.bin/truss/sparc64-fbsd.c b/usr.bin/truss/sparc64-fbsd.c
index 4aa512d..429fa24 100644
--- a/usr.bin/truss/sparc64-fbsd.c
+++ b/usr.bin/truss/sparc64-fbsd.c
@@ -67,8 +67,6 @@ static const char rcsid[] =
 #include "syscall.h"
 #include "extern.h"
 
-static int cpid = -1;
-
 #include "syscalls.h"
 
 static int nsyscalls = sizeof(syscallnames) / sizeof(syscallnames[0]);
@@ -82,30 +80,35 @@ static int nsyscalls = sizeof(syscallnames) / sizeof(syscallnames[0]);
  * 'struct syscall' describes the system call; it may be NULL, however,
  * if we don't know about this particular system call yet.
  */
-static struct freebsd_syscall {
+struct freebsd_syscall {
 	struct syscall *sc;
 	const char *name;
 	int number;
 	unsigned long *args;
 	int nargs;	/* number of arguments -- *not* number of words! */
 	char **s_args;	/* the printable arguments */
-} fsc;
+};
+
+static struct freebsd_syscall *
+alloc_fsc(void)
+{
+
+	return (malloc(sizeof(struct freebsd_syscall)));
+}
 
 /* Clear up and free parts of the fsc structure. */
-static __inline void
-clear_fsc(void)
+static void
+free_fsc(struct freebsd_syscall *fsc)
 {
 	int i;
 
-	if (fsc.args)
-		free(fsc.args);
-	if (fsc.s_args) {
-		for (i = 0; i < fsc.nargs; i++)
-			if (fsc.s_args[i])
-				free(fsc.s_args[i]);
-		free(fsc.s_args);
+	free(fsc->args);
+	if (fsc->s_args) {
+		for (i = 0; i < fsc->nargs; i++)
+			free(fsc->s_args[i]);
+		free(fsc->s_args);
 	}
-	memset(&fsc, 0, sizeof(fsc));
+	free(fsc);
 }
 
 /*
@@ -120,15 +123,15 @@ sparc64_syscall_entry(struct trussinfo *trussinfo, int nargs)
 {
 	struct ptrace_io_desc iorequest;
 	struct reg regs;
+	struct freebsd_syscall *fsc;
 	struct syscall *sc;
+	lwpid_t tid;
 	int i, syscall_num;
 	int indir;	/* indirect system call */
 
-	clear_fsc();
-
-	cpid = trussinfo->curthread->tid;
+	tid = trussinfo->curthread->tid;
 
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
 		return;
 	}
@@ -145,24 +148,27 @@ sparc64_syscall_entry(struct trussinfo *trussinfo, int nargs)
 		syscall_num = regs.r_out[0];
 	}
 
-	fsc.number = syscall_num;
-	fsc.name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
+	fsc = alloc_fsc();
+	if (fsc == NULL)
+		return;
+	fsc->number = syscall_num;
+	fsc->name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
 	    NULL : syscallnames[syscall_num];
-	if (!fsc.name) {
+	if (!fsc->name) {
 		fprintf(trussinfo->outfile, "-- UNKNOWN SYSCALL %d --\n",
 		    syscall_num);
 	}
 
-	if (fsc.name && (trussinfo->flags & FOLLOWFORKS) &&
-	    (strcmp(fsc.name, "fork") == 0 ||
-	    strcmp(fsc.name, "rfork") == 0 ||
-	    strcmp(fsc.name, "vfork") == 0))
+	if (fsc->name && (trussinfo->flags & FOLLOWFORKS) &&
+	    (strcmp(fsc->name, "fork") == 0 ||
+	    strcmp(fsc->name, "rfork") == 0 ||
+	    strcmp(fsc->name, "vfork") == 0))
 		trussinfo->curthread->in_fork = 1;
 
 	if (nargs == 0)
 		return;
 
-	fsc.args = malloc((1 + nargs) * sizeof(unsigned long));
+	fsc->args = malloc((1 + nargs) * sizeof(unsigned long));
 	switch (nargs) {
 	default:
 		/*
@@ -183,38 +189,38 @@ sparc64_syscall_entry(struct trussinfo *trussinfo, int nargs)
 		iorequest.piod_op = PIOD_READ_D;
 		iorequest.piod_offs = (void *)(regs.r_out[6] + SPOFF +
 		    offsetof(struct frame, fr_pad[6]));
-		iorequest.piod_addr = &fsc.args[6];
-		iorequest.piod_len = (nargs - 6) * sizeof(fsc.args[0]);
-		ptrace(PT_IO, cpid, (caddr_t)&iorequest, 0);
+		iorequest.piod_addr = &fsc->args[6];
+		iorequest.piod_len = (nargs - 6) * sizeof(fsc->args[0]);
+		ptrace(PT_IO, tid, (caddr_t)&iorequest, 0);
 		if (iorequest.piod_len == 0)
 			return;
-	case 6:	fsc.args[5] = regs.r_out[5];
-	case 5:	fsc.args[4] = regs.r_out[4];
-	case 4:	fsc.args[3] = regs.r_out[3];
-	case 3:	fsc.args[2] = regs.r_out[2];
-	case 2:	fsc.args[1] = regs.r_out[1];
-	case 1:	fsc.args[0] = regs.r_out[0];
+	case 6:	fsc->args[5] = regs.r_out[5];
+	case 5:	fsc->args[4] = regs.r_out[4];
+	case 4:	fsc->args[3] = regs.r_out[3];
+	case 3:	fsc->args[2] = regs.r_out[2];
+	case 2:	fsc->args[1] = regs.r_out[1];
+	case 1:	fsc->args[0] = regs.r_out[0];
 	case 0:
 		break;
 	}
 
 	if (indir)
-		memmove(&fsc.args[0], &fsc.args[1], (nargs - 1) *
-		    sizeof(fsc.args[0]));
+		memmove(&fsc->args[0], &fsc->args[1], (nargs - 1) *
+		    sizeof(fsc->args[0]));
 
-	sc = get_syscall(fsc.name);
+	sc = get_syscall(fsc->name);
 	if (sc)
-		fsc.nargs = sc->nargs;
+		fsc->nargs = sc->nargs;
 	else {
 #if DEBUG
 		fprintf(trussinfo->outfile, "unknown syscall %s -- setting "
-		    "args to %d\n", fsc.name, nargs);
+		    "args to %d\n", fsc->name, nargs);
 #endif
-		fsc.nargs = nargs;
+		fsc->nargs = nargs;
 	}
 
-	fsc.s_args = calloc(1, (1 + fsc.nargs) * sizeof(char *));
-	fsc.sc = sc;
+	fsc->s_args = calloc(1, (1 + fsc->nargs) * sizeof(char *));
+	fsc->sc = sc;
 
 	/*
 	 * At this point, we set up the system call arguments.
@@ -224,19 +230,19 @@ sparc64_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	 * passed in *and* out, however.
 	 */
 
-	if (fsc.name) {
+	if (fsc->name) {
 #if DEBUG
-		fprintf(stderr, "syscall %s(", fsc.name);
+		fprintf(stderr, "syscall %s(", fsc->name);
 #endif
-		for (i = 0; i < fsc.nargs; i++) {
+		for (i = 0; i < fsc->nargs; i++) {
 #if DEBUG
 			fprintf(stderr, "0x%x%s", sc ?
-			    fsc.args[sc->args[i].offset] : fsc.args[i],
-			    i < (fsc.nargs - 1) ? "," : "");
+			    fsc->args[sc->args[i].offset] : fsc->args[i],
+			    i < (fsc->nargs - 1) ? "," : "");
 #endif
 			if (sc && !(sc->args[i].type & OUT)) {
-				fsc.s_args[i] = print_arg(&sc->args[i],
-				    fsc.args, 0, trussinfo);
+				fsc->s_args[i] = print_arg(&sc->args[i],
+				    fsc->args, 0, trussinfo);
 			}
 		}
 #if DEBUG
@@ -248,30 +254,29 @@ sparc64_syscall_entry(struct trussinfo *trussinfo, int nargs)
 	fprintf(trussinfo->outfile, "\n");
 #endif
 
-	if (fsc.name != NULL && (strcmp(fsc.name, "execve") == 0 ||
-	    strcmp(fsc.name, "exit") == 0)) {
+	if (fsc->name != NULL && (strcmp(fsc->name, "execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0)) {
 		/*
 		 * XXX
 		 * This could be done in a more general
 		 * manner but it still wouldn't be very pretty.
 		 */
-		if (strcmp(fsc.name, "execve") == 0) {
+		if (strcmp(fsc->name, "execve") == 0) {
 			if ((trussinfo->flags & EXECVEARGS) == 0) {
-				if (fsc.s_args[1]) {
-					free(fsc.s_args[1]);
-					fsc.s_args[1] = NULL;
+				if (fsc->s_args[1]) {
+					free(fsc->s_args[1]);
+					fsc->s_args[1] = NULL;
 				}
 			}
 			if ((trussinfo->flags & EXECVEENVS) == 0) {
-				if (fsc.s_args[2]) {
-					free(fsc.s_args[2]);
-					fsc.s_args[2] = NULL;
+				if (fsc->s_args[2]) {
+					free(fsc->s_args[2]);
+					fsc->s_args[2] = NULL;
 				}
 			}
 		}
 	}
-
-	return;
+	trussinfo->curthread->fsc = fsc;
 }
 
 /*
@@ -285,16 +290,18 @@ long
 sparc64_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 {
 	struct reg regs;
+	struct freebsd_syscall *fsc;
 	struct syscall *sc;
+	lwpid_t tid;
 	long retval;
 	int errorp, i;
 
-	if (fsc.name == NULL)
+	if (trussinfo->curthread->fsc == NULL)
 		return (-1);
 
-	cpid = trussinfo->curthread->tid;
+	tid = trussinfo->curthread->tid;
 
-	if (ptrace(PT_GETREGS, cpid, (caddr_t)&regs, 0) < 0) {
+	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
 		fprintf(trussinfo->outfile, "\n");
 		return (-1);
 	}
@@ -307,10 +314,11 @@ sparc64_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 	 * stand some significant cleaning.
 	 */
 
-	sc = fsc.sc;
+	fsc = trussinfo->curthread->fsc;
+	sc = fsc->sc;
 	if (!sc) {
-		for (i = 0; i < fsc.nargs; i++)
-			asprintf(&fsc.s_args[i], "0x%lx", fsc.args[i]);
+		for (i = 0; i < fsc->nargs; i++)
+			asprintf(&fsc->s_args[i], "0x%lx", fsc->args[i]);
 	} else {
 		/*
 		 * Here, we only look for arguments that have OUT masked in --
@@ -325,18 +333,18 @@ sparc64_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 				 */
 				if (errorp) {
 					asprintf(&temp, "0x%lx",
-					    fsc.args[sc->args[i].offset]);
+					    fsc->args[sc->args[i].offset]);
 				} else {
 					temp = print_arg(&sc->args[i],
-					    fsc.args, retval, trussinfo);
+					    fsc->args, retval, trussinfo);
 				}
-				fsc.s_args[i] = temp;
+				fsc->s_args[i] = temp;
 			}
 		}
 	}
 
-	if (fsc.name != NULL && (strcmp(fsc.name, "execve") == 0 ||
-	    strcmp(fsc.name, "exit") == 0))
+	if (fsc->name != NULL && (strcmp(fsc->name, "execve") == 0 ||
+	    strcmp(fsc->name, "exit") == 0))
 		trussinfo->curthread->in_syscall = 1;
 
 	/*
@@ -344,9 +352,9 @@ sparc64_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
 	 * but that complicates things considerably.
 	 */
 
-	print_syscall_ret(trussinfo, fsc.name, fsc.nargs, fsc.s_args, errorp,
-	    retval, fsc.sc);
-	clear_fsc();
+	print_syscall_ret(trussinfo, fsc->name, fsc->nargs, fsc->s_args, errorp,
+	    retval, fsc->sc);
+	free_fsc(fsc);
 
 	return (retval);
 }
diff --git a/usr.bin/truss/syscalls.c b/usr.bin/truss/syscalls.c
index 4fba0cc..0afd083 100644
--- a/usr.bin/truss/syscalls.c
+++ b/usr.bin/truss/syscalls.c
@@ -1120,20 +1120,21 @@ print_syscall(struct trussinfo *trussinfo, const char *name, int nargs,
 	if (trussinfo->flags & FOLLOWFORKS)
 		len += fprintf(trussinfo->outfile, "%5d: ", trussinfo->pid);
 
-	if (name != NULL && (strcmp(name, "execve") == 0||
+	if (name != NULL && (strcmp(name, "execve") == 0 ||
 	    strcmp(name, "exit") == 0)) {
-		clock_gettime(CLOCK_REALTIME, &trussinfo->after);
+		clock_gettime(CLOCK_REALTIME, &trussinfo->curthread->after);
 	}
 
 	if (trussinfo->flags & ABSOLUTETIMESTAMPS) {
-		timespecsubt(&trussinfo->after, &trussinfo->start_time,
-		    &timediff);
+		timespecsubt(&trussinfo->curthread->after,
+		    &trussinfo->start_time, &timediff);
 		len += fprintf(trussinfo->outfile, "%ld.%09ld ",
 		    (long)timediff.tv_sec, timediff.tv_nsec);
 	}
 
 	if (trussinfo->flags & RELATIVETIMESTAMPS) {
-		timespecsubt(&trussinfo->after, &trussinfo->before, &timediff);
+		timespecsubt(&trussinfo->curthread->after,
+		    &trussinfo->curthread->before, &timediff);
 		len += fprintf(trussinfo->outfile, "%ld.%09ld ",
 		    (long)timediff.tv_sec, timediff.tv_nsec);
 	}
@@ -1163,8 +1164,9 @@ print_syscall_ret(struct trussinfo *trussinfo, const char *name, int nargs,
 	if (trussinfo->flags & COUNTONLY) {
 		if (!sc)
 			return;
-		clock_gettime(CLOCK_REALTIME, &trussinfo->after);
-		timespecsubt(&trussinfo->after, &trussinfo->before, &timediff);
+		clock_gettime(CLOCK_REALTIME, &trussinfo->curthread->after);
+		timespecsubt(&trussinfo->curthread->after,
+		    &trussinfo->curthread->before, &timediff);
 		timespecadd(&sc->time, &timediff, &sc->time);
 		sc->ncalls++;
 		if (errorp)
diff --git a/usr.bin/truss/truss.h b/usr.bin/truss/truss.h
index 7dd87f5..dcc86a5 100644
--- a/usr.bin/truss/truss.h
+++ b/usr.bin/truss/truss.h
@@ -41,6 +41,9 @@ struct threadinfo
 	lwpid_t tid;
 	int in_syscall;
 	int in_fork;
+	void *fsc;
+	struct timespec before;
+	struct timespec after;
 };
 
 struct trussinfo
@@ -53,8 +56,6 @@ struct trussinfo
 	FILE *outfile;
 
 	struct timespec start_time;
-	struct timespec before;
-	struct timespec after;
 
 	struct threadinfo *curthread;