Spell -t option's argument by name.

usr.bin/kdump/kdump.1

@@ -44,7 +44,7 @@
 .Op Fl f Ar trfile
 .Op Fl m Ar maxdata
 .Op Fl p Ar pid
-.Op Fl t Op cnistuw
+.Op Fl t Ar trstr
 .Sh DESCRIPTION
 The
 .Nm
@@ -103,7 +103,7 @@ GIDs, dates etc. symbolically instead of numerically.
 Suppress display of I/O data.
 .It Fl T
 Display absolute timestamps for each entry (seconds since epoch).
-.It Fl t Ar cnistuw
+.It Fl t Ar trstr
 See the
 .Fl t
 option of

usr.bin/kdump/kdump.c

@@ -1361,6 +1361,6 @@ void
 usage(void)
 {
 	fprintf(stderr, "usage: kdump [-dEnlHRrsT] [-f trfile] "
-	    "[-m maxdata] [-p pid] [-t [cnistuw]]\n");
+	    "[-m maxdata] [-p pid] [-t trstr]\n");
 	exit(1);
 }

usr.bin/ktrace/ktrace.1

@@ -43,11 +43,11 @@
 .Op Fl aCcdi
 .Op Fl f Ar trfile
 .Op Fl g Ar pgrp | Fl p Ar pid
-.Op Fl t Ar cnistuw
+.Op Fl t Ar trstr
 .Nm
 .Op Fl adi
 .Op Fl f Ar trfile
-.Op Fl t Ar cnistuw
+.Op Fl t Ar trstr
 .Ar command
 .Sh DESCRIPTION
 The
@@ -105,7 +105,7 @@ processes.
 Enable (disable) tracing on the indicated process id (only one
 .Fl p
 flag is permitted).
-.It Fl t Ar cnistuw
+.It Fl t Ar trstr
 The string argument represents the kernel trace points, one per letter.
 The following table equates the letters with the tracepoints:
 .Pp

usr.bin/ktrace/ktrace.c

@@ -194,8 +194,8 @@ static void
 usage(void)
 {
 	(void)fprintf(stderr, "%s\n%s\n",
-"usage: ktrace [-aCcdi] [-f trfile] [-g pgrp | -p pid] [-t cnistuw]",
-"       ktrace [-adi] [-f trfile] [-t cnistuw] command");
+"usage: ktrace [-aCcdi] [-f trfile] [-g pgrp | -p pid] [-t trstr]",
+"       ktrace [-adi] [-f trfile] [-t trstr] command");
 	exit(1);
 }