dwdiff - a delimited word diff program

       G.P. Halkes <dwdiff@ghalkes.nl>

       If  you  think  you  have  found  a  bug,  please  check  that you are using the latest version of dwdiff
       <http://os.ghalkes.nl/dwdiff.html>.  When  reporting  bugs,  please  include  a  minimal   example   that
       demonstrates the problem.

       Copyright © 2006-2017 G.P. Halkes and others
       dwdiff is licensed under the GNU General Public License version 3.
       For  more  details  on  the license, see the file COPYING in the documentation directory. On Un*x systems
       this is usually /usr/share/doc/dwdiff-$VERSION$.

dwdiff  is a diff program that operates at the word level instead of the line level. It is different from
       wdiff in that it allows the user to specify what should be considered whitespace, and in that it takes an
       optional list of characters that should be considered delimiters. Delimiters are single  characters  that
       are  treated  as if they are words, even when there is no whitespace separating them from preceding words
       or delimiters. dwdiff is mostly command-line compatible with wdiff. Only the --autopager, --terminal  and
       --avoid-wraps options are not supported.

       The  default  output  from  dwdiff  is  the  new text, with the deleted and inserted parts annotated with
       markers. Command line options are available to change both what is printed, and the markers.

       dwdiff - a delimited word diff program

dwdiff accepts the following options (Note that all strings will first be escape expanded.  All  standard
       \-escapes are supported, as well as \u and \U Unicode escapes):

       -h, --help
              Display a short help message.

       -v, --version
              Print version and copyright information.

       -ddelimiters, --delimiters=delimiters
              Specify a list of characters to be used as delimiters. The default is empty.

       -P, --punctuation
              Use  punctuation  characters as delimiters. The exact set of punctuation characters depends on the
              current locale.

       -Wwhitespace, --white-space=whitespace
              Specify a list of characters to be used as whitespace. The default set  of  whitespace  characters
              depends on the current locale.

       -u, --diff-input
              Interpret  the  input as the output from diff in the Unified Diff format (usually produced by diff-u). In this case only one input file is allowed. This option allows reformating diff output  with
              dwdiff, and is useful for example to post-process the output of svndiff.

       -1, --no-deleted
              Suppress printing of words deleted from the first file.

       -2, --no-inserted
              Suppress printing of words inserted in the second file.

       -3, --no-common
              Suppress printing of words common to both files.

       -L[width], --line-numbers[=width]
              Show line numbers at the start of each line. The line numbers displayed are the line number in the
              old  file  and  the  line  number in the new file respectively. The optional width argument is the
              minimum number of positions per line number.

       -Cnum, --context=num
              Show num lines of context before and after each changes. A line with only --  is  printed  between
              blocks of changes.

       -s, --statistics
              Print  statistics  when  done. The numbers printed include the number of words from in both files,
              the number of deleted words, the number of inserted words, and the number of  changed  words.  The
              number  of  changed  words is counted as the number of words that are removed from the first file,
              and the number of words that replace them from the second file. All  of  these  numbers  are  also
              expressed as a percentage of the total number of words in the file the words came from.

       -i, --ignore-case
              Ignore differences in case when comparing words. This option is only available if the diff program
              that is called provides it.

       -I, --ignore-formatting
              Ignore  differences  in  formatting  of  characters.  This  option  switches  to using the Unicode
              compatibility  decomposition  instead  of  the   canonical   decomposition.    The   compatibility
              decomposition  discards  formatting  information.  For example, the ligature fi will be decomposed
              into two separate characters for the purposes of comparison. However, also  super-  and  subscript
              will be regarded equal as well as different rotations of the same character.

       -c[spec], --color[=spec]
              Color  mode.  The  optional  spec  can  be  used  to  customize  the  colors.   spec  consists  of
              [delete],[insert]. If either is omited it will be set to its default color (bright red  or  bright
              green respectively). Both parts of the spec consist of [foreground][:background]. To obtain a list
              of  permissible  color  names,  use  the word ``list'' as spec. Alternatively, you can specify any
              escape sequence to set attributes as a color by prepending e:.

              The standard markers for the begin and end of deleted and inserted text are  suppressed,  but  any
              markers specified on the command line will still be printed.

       -l, --less-mode
              As -p but also overstrike deleted whitespace.

       -p, --printer
              Use  overstriking  with  an  underscore and bold text to emphasize changes. This is implemented by
              first printing the underscore or a duplicate of  the  character  to  be  printed,  followed  by  a
              backspace,  followed by the character.  On regular terminals you won't see any effect. The less(1)
              command will however show underlined and bold text.

              The standard markers for the begin and end of deleted and inserted text are  suppressed,  but  any
              markers specified on the command line will still be printed.

       -mnum, --match-context=num
              Use num words of context before and after words for matching. Words in the old text will then only
              match words in the new text if words surrounding them are also equal. This improves the output for
              dwdiff  for  large  changes  with frequently occurring words. However, using context requires more
              disk space and more processing time. The default value is 1. Set this option to 0 to revert to the
              pre 1.5 behavior.

       --aggregate-changes
              Allow multiple close changes to be  treated  as  one  change,  if  context  words  are  used  (see
              --match-context).  This  option  reduces  the  processing time as the changes reported by the diff
              program are not post-processed to give more precise results.

       -Aalgorithm, --algorithm=algorithm
              Select the algorithm to be used for determining differences. There are three possible  values  for
              algorithm:  best,  which  tries  to  find  the  minimal  set of changes, normal, which trades some
              optimality for speed, and fast, which assumes that the input is large and contains few changes. By
              default the normal algorithm is used.

       -S[marker], --paragraph-separator[=marker]
              Show insertion or deletion of blocks of lines with only whitespace characters.  A  special  marker
              is inserted into the output to indicate these blocks. The default marker is --.

       --wdiff-output
              Create  wdiff  compatible  output.  The  dwdiff  program  uses a different output algorithm, which
              provides a more intuitive output.

       -wstring, --start-delete=string
              Specify a string to mark begin of deleted text. The default is [-.

       -xstring, --stop-delete=string
              Specify a string to mark end of deleted text. The default is -].

       -ystring, --start-insert=string
              Specify a string to mark begin of inserted text. The default is {+.

       -zstring, --stop-insert=string
              Specify a string to mark end of inserted text. The default is +}.

       -R, --repeat-markers
              Repeat the begin and end markers at the start and end of line if a change crosses a newline.

       --profile=name
              Load the profile with name name from the .dwdiffrc file in the user's  home  directory.  Only  the
              last  profile  named  is actually read, unless it is followed by a --no-profile option. By default
              the profile named default is read.

       --no-profile
              Disable reading of profiles, unless followed by another  --profile  option.   This  also  disables
              reading the default profile.

       A single dash (-) as a file can be used to denote standard input. Only one file can be read from standard
       input.  To  stop dwdiff from interpreting file names that start with a dash as options, one can specify a
       double dash (--) after which dwdiff will interpret any following arguments as files to read.

       The exit status of dwdiff indicates the result of the comparison: 0 if the files are the same, 1  if  the
       files are different. Should an error occur, dwdiff will exit with status 2.

       Since  version  2.1.0,  dwdiff allows users to create profiles. A profile is a set of options that can be
       loaded using the --profile option. Profiles are specified in the .dwdiffrc in the user's home  directory.
       The format of the .dwdiffrc file is as follows:

       A  line  contains  either  a profile header (a text enclosed in []) or a long option name without leading
       dashes, optionally followed by it's argument. Arguments are stripped of whitespace surrounding it. If  an
       argument  starts  and ends with matching double or single quotes, these are removed as well. Comments can
       be included by starting a line with a hash mark (#).

       If no profile is specified, the profile named default will be loaded, unless the --no-profile  option  is
       specified. Here is an example .dwdiffrc:

            [default]
            color red,blue
            punctuation

            [html]
            start-delete <span style="color=red">
            stop-delete </span>
            start-insert <span style="color=green">
            stop-insert </span>

            [space-only]
            # Use only a space as whitespace.
            white-space " "

dwfilter(1), wdiff(1), diff(1)

$VERSION$                                          2018/12/03                                          DWDIFF(1)

dwdiff [OPTIONS] OLDFILENEWFILEdwdiff [OPTIONS] --diff-input [DIFFFILE]