===================================================================
RCS file: /cvs/docbook2mdoc/docbook2mdoc.1,v
retrieving revision 1.11
retrieving revision 1.13
diff -u -p -r1.11 -r1.13
--- docbook2mdoc/docbook2mdoc.1	2019/04/09 16:57:29	1.11
+++ docbook2mdoc/docbook2mdoc.1	2019/04/23 15:47:23	1.13
@@ -1,4 +1,4 @@
-.\" $Id: docbook2mdoc.1,v 1.11 2019/04/09 16:57:29 schwarze Exp $
+.\" $Id: docbook2mdoc.1,v 1.13 2019/04/23 15:47:23 schwarze Exp $
 .\"
 .\" Copyright (c) 2014 Kristaps Dzonsons <kristaps@bsd.lv>
 .\" Copyright (c) 2019 Ingo Schwarze <schwarze@openbsd.org>
@@ -15,7 +15,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: April 9 2019 $
+.Dd $Mdocdate: April 23 2019 $
 .Dt DOCBOOK2MDOC 1
 .Os
 .Sh NAME
@@ -24,6 +24,7 @@
 .Sh SYNOPSIS
 .Nm docbook2mdoc
 .Op Fl W
+.Op Fl T Cm mdoc | tree | lint
 .Op Ar file
 .Sh DESCRIPTION
 The
@@ -40,8 +41,36 @@ is
 .Sq Cm \-
 or omitted, standard input is used.
 .Pp
-The arguments are as follows:
-.Bl -tag -width Ds
+The options are as follows:
+.Bl -tag -width 2n
+.It Fl T
+Select the output mode.
+The following arguments are supported:
+.Bl -tag -width 4n
+.It Cm mdoc
+Translate the input to
+.Xr mdoc 7 .
+This is the default.
+.It Cm tree
+Dump a human-readable representation of the parse tree.
+Each output line shows one tree node.
+Child nodes are indented with respect to their parent node.
+The columns are:
+.Bl -enum -width 2n
+.It
+A hyphen if the node follows the previous node
+without intervening whitespace.
+.It
+The node type.
+.It
+For text nodes, the text contents.
+For other nodes, the attributes, if any.
+.El
+.It Cm lint
+Do not produce any output, only error messages.
+Can be combined with
+.Fl W .
+.El
 .It Fl W
 Report warnings on standard error output, and if any occur, raise the
 .Sx EXIT STATUS
@@ -72,6 +101,16 @@ Internal subset declaration to define an XML entity.
 .Ec >
 Internal subset declaration to define an XML entity using an external
 .Ar file .
+.It Eo <!
+.Ic DOCTYPE No ...
+.Bo
+.Eo " <!" Ic ENTITY No % Ar name Cm SYSTEM Qo Ar file Qc Ec >
+.Pf % Ar name No \&
+.Bc
+.Ec >
+Internal subset declaration to include an external
+.Ar file
+that is supposed to contain entity declarations.
 .It Eo < Ic mml : Ns ... Ec >
 Elements from the MathML namespace.
 These are translated to