GDIFFMK(1)		    General Commands Manual		    GDIFFMK(1)



NAME
       gdiffmk - mark differences between groff/nroff/troff files

SYNOPSIS
       gdiffmk [ -aaddmark ] [ -cchangemark ] [ -ddeletemark ] [ -D [ -B ]
	       [ -Mmark1 mark2 ] ] [ -xdiffcmd ] [ -- ] [ --help ]
	       [ --version ] file1 file2 [ output ]

DESCRIPTION
       gdiffmk	compares  two groff(1), nroff(1), or troff(1) documents, file1
       and file2, and creates an output which  is  file2  with	added  `margin
       character' (.mc) commands that indicate the differences.

       If  the output filename is present, the output is written there.	 If it
       is - or absent the output is written to the standard output.

       If the file1 or file2 argument is - the standard input is read for that
       input.  Clearly both cannot be -.

       Note that the output is not necessarily compatible with all macro pack-
       ages and all preprocessors.  See the BUGS section below.

OPTIONS
       -aaddmark
	      Use the addmark for source lines not in  file1  but  present  in
	      file2.  Default: +.

       -B     By  default,  the deleted texts marked by the -D option end with
	      an added troff break command, .br, to ensure that the  deletions
	      are  marked  properly.   This  is the only way to guarantee that
	      deletions and small changes get flagged.	 This  option  directs
	      the program not to insert these breaks; it makes no sense to use
	      it without -D.

       -cchangemark
	      Use the changemark for changed source lines.  Default: |.

       -ddeletemark
	      Use the deletemark for deleted source lines.  Default: *.

       -D     Show  the	 deleted  portions  from  changed  and	deleted	 text.
	      Default delimiting marks: [[ .... ]].

       -Mmark1 mark2
	      Change  the  delimiting  marks  for  the -D option.  It makes no
	      sense to use this option without -D.

       -xdiffcmd
	      Use the diffcmd command to perform the comparison of  file1  and
	      file2.  In particular, diffcmd should accept the GNU diff -Dname
	      option.  Default: diff(1).

       --     All the following arguments are treated as file names,  even  if
	      they begin with -.

       --help Print a usage message on standard error output and exit.

       --version
	      Print version information on the standard output and exit.

BUGS
       The  output  is	not necessarily compatible with all macro packages and
       all preprocessors.  A workaround that is often successful against  pre-
       processor  problems  is	to  run	 gdiffmk on the output of all the pre-
       processors instead of the input source.

       gdiffmk relies on the -Dname option of GNU diff(1)  to  make  a	merged
       `#ifdef'	 output	 format.  It hasn't been tested whether other versions
       of diff(1) do support this option.  See also the -xdiffcmd option.

       Report bugs to bug-groff@gnu.org.  Include a  complete,	self-contained
       example that will allow the bug to be reproduced, and say which version
       of gdiffmk you are using.

AUTHORS
       This  document  was  written  and  is  maintained   by	Mike   Bianchi
       <MBianchi@Foveal.com>.

       This document is distributed under the terms of the FDL (GNU Free Docu-
       mentation License) version 1.1 or later.	 You should  have  received  a
       copy of the FDL on your system, it is also available on-line at the GNU
       copyleft site <http://www.gnu.org/copyleft/fdl.html>.

       gdiffmk is part of the groff GNU free software project.	All  parts  of
       the groff package are protected by GNU copyleft licenses.  The software
       files are distributed under the terms of the GNU General Public License
       (GPL), while the documentation files mostly use the GNU Free Documenta-
       tion License (FDL).

COPYRIGHT
       Copyright (C) 2004, 2005, 2008 Free Software Foundation, Inc.

       gdiffmk is free software; you can  redistribute	it  and/or  modify  it
       under  the  terms of the GNU General Public License as published by the
       Free Software Foundation, either version 3 of the License, or (at  your
       option) any later version.

       gdiffmk	is distributed in the hope that it will be useful, but WITHOUT
       ANY WARRANTY; without even the implied warranty of  MERCHANTABILITY  or
       FITNESS	FOR  A PARTICULAR PURPOSE.  See the GNU General Public License
       for more details.

       You should have received a copy of the GNU General Public License along
       with this program. If not, see <http://www.gnu.org/licenses/>.

SEE ALSO
       groff(1), nroff(1), gtroff(1), diff(1)



Groff Version 1.22.2		7 February 2013			    GDIFFMK(1)