docbook2X converts DocBook to man pages in two steps:
The DocBook source is converted by a stylesheet into an intermediate XML format, Man-XML.
Man-XML is simpler than DocBook and closer to the man page format; it is intended to make the stylesheets' job easier.
The stylesheet for this purpose has the public ID:
-//Steve Cheng//DOCUMENT DocBook Man-page Stylesheet//EN
Alternatively, you can refer to the stylesheet with this URI:
http://docbook2x.sf.net/latest/xslt/man/docbook.xsl
Run this stylesheet with db2x_xsltproc.
Man-XML is converted to the actual man pages by db2x_manxml.
The docbook2man command does both steps automatically, but if any problems occur, you can see the errors more clearly if you do each step separately:
$ db2x_xsltproc -s man mydoc.xml -o mydoc.mxml $ db2x_manxml mydoc.mxml