diff --git a/usr.bin/truss/syscalls.c b/usr.bin/truss/syscalls.c
index 9a3b9c7e42ab..bec0dc0f33ec 100644
--- a/usr.bin/truss/syscalls.c
+++ b/usr.bin/truss/syscalls.c
@@ -397,6 +397,30 @@ static struct xlat kevent_flags[] = {
 	X(EV_DROP) X(EV_FLAG1) X(EV_ERROR) X(EV_EOF) XEND
 };
 
+static struct xlat kevent_user_ffctrl[] = {
+	X(NOTE_FFNOP) X(NOTE_FFAND) X(NOTE_FFOR) X(NOTE_FFCOPY)
+	XEND
+};
+
+static struct xlat kevent_rdwr_fflags[] = {
+	X(NOTE_LOWAT) X(NOTE_FILE_POLL) XEND
+};
+
+static struct xlat kevent_vnode_fflags[] = {
+	X(NOTE_DELETE) X(NOTE_WRITE) X(NOTE_EXTEND) X(NOTE_ATTRIB)
+	X(NOTE_LINK) X(NOTE_RENAME) X(NOTE_REVOKE) XEND
+};
+
+static struct xlat kevent_proc_fflags[] = {
+	X(NOTE_EXIT) X(NOTE_FORK) X(NOTE_EXEC) X(NOTE_TRACK) X(NOTE_TRACKERR)
+	X(NOTE_CHILD) XEND
+};
+
+static struct xlat kevent_timer_fflags[] = {
+	X(NOTE_SECONDS) X(NOTE_MSECONDS) X(NOTE_USECONDS) X(NOTE_NSECONDS)
+	XEND
+};
+
 static struct xlat poll_flags[] = {
 	X(POLLSTANDARD) X(POLLIN) X(POLLPRI) X(POLLOUT) X(POLLERR)
 	X(POLLHUP) X(POLLNVAL) X(POLLRDNORM) X(POLLRDBAND)
@@ -742,6 +766,64 @@ strsig2(int sig)
 	return (ret);
 }
 
+static void
+print_kevent(FILE *fp, struct kevent *ke, int input)
+{
+
+	switch (ke->filter) {
+	case EVFILT_READ:
+	case EVFILT_WRITE:
+	case EVFILT_VNODE:
+	case EVFILT_PROC:
+	case EVFILT_TIMER:
+	case EVFILT_PROCDESC:
+		fprintf(fp, "%ju", (uintmax_t)ke->ident);
+		break;
+	case EVFILT_SIGNAL:
+		fputs(strsig2(ke->ident), fp);
+		break;
+	default:
+		fprintf(fp, "%p", (void *)ke->ident);
+	}
+	fprintf(fp, ",%s,%s,", xlookup(kevent_filters, ke->filter),
+	    xlookup_bits(kevent_flags, ke->flags));
+	switch (ke->filter) {
+	case EVFILT_READ:
+	case EVFILT_WRITE:
+		fputs(xlookup_bits(kevent_rdwr_fflags, ke->fflags), fp);
+		break;
+	case EVFILT_VNODE:
+		fputs(xlookup_bits(kevent_vnode_fflags, ke->fflags), fp);
+		break;
+	case EVFILT_PROC:
+	case EVFILT_PROCDESC:
+		fputs(xlookup_bits(kevent_proc_fflags, ke->fflags), fp);
+		break;
+	case EVFILT_TIMER:
+		fputs(xlookup_bits(kevent_timer_fflags, ke->fflags), fp);
+		break;
+	case EVFILT_USER: {
+		int ctrl, data;
+
+		ctrl = ke->fflags & NOTE_FFCTRLMASK;
+		data = ke->fflags & NOTE_FFLAGSMASK; 
+		if (input) {
+			fputs(xlookup(kevent_user_ffctrl, ctrl), fp);
+			if (ke->fflags & NOTE_TRIGGER)
+				fputs("|NOTE_TRIGGER", fp);
+			if (data != 0)
+				fprintf(fp, "|%#x", data);
+		} else {
+			fprintf(fp, "%#x", data);
+		}
+		break;
+	}
+	default:
+		fprintf(fp, "%#x", ke->fflags);
+	}
+	fprintf(fp, ",%p,%p", (void *)ke->data, (void *)ke->udata);
+}
+
 /*
  * print_arg
  * Converts a syscall argument into a string.  Said string is
@@ -1281,14 +1363,10 @@ print_arg(struct syscall_args *sc, unsigned long *args, long retval,
 		if (numevents >= 0 && get_struct(pid, (void *)args[sc->offset],
 		    ke, bytes) != -1) {
 			fputc('{', fp);
-			for (i = 0; i < numevents; i++)
-				fprintf(fp, " %p,%s,%s,%d,%p,%p",
-				    (void *)ke[i].ident,
-				    xlookup(kevent_filters, ke[i].filter),
-				    xlookup_bits(kevent_flags, ke[i].flags),
-				    ke[i].fflags,
-				    (void *)ke[i].data,
-				    (void *)ke[i].udata);
+			for (i = 0; i < numevents; i++) {
+				fputc(' ', fp);
+				print_kevent(fp, &ke[i], sc->offset == 1);
+			}
 			fputs(" }", fp);
 		} else {
 			fprintf(fp, "0x%lx", args[sc->offset]);