--- ctm_rmail/ctm_rmail.8.orig	2018-10-27 15:56:22 UTC
+++ ctm_rmail/ctm_rmail.8
@@ -7,7 +7,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd January 24, 1995
+.Dd December 23, 2018
 .Dt CTM_MAIL 8
 .Os
 .Sh NAME
@@ -35,6 +35,7 @@ deltas via mail
 .Op Fl p Ar piecedir
 .Op Fl d Ar deltadir
 .Op Fl b Ar basedir
+.Op Fl B Ar backup_dir
 .Op Ar
 .Sh DESCRIPTION
 In conjunction with the
@@ -191,6 +192,10 @@ file in
 (or if
 .Li .ctm_status
 does not exist).
+.It Fl B Ar backup_dir
+Specify a backup directory for use by
+.Nm ctm
+.Fl B
 .It Fl D
 Delete deltas after successful application by
 .Xr ctm .