Provided by: latexdiff_1.1.1-1_all bug

NAME

       latexdiff - determine and markup differences between two latex files

SYNOPSIS

       latexdiff [ OPTIONS ] old.tex new.tex > diff.tex

DESCRIPTION

       Briefly, latexdiff is a utility program to aid in the management of revisions of latex
       documents. It compares two valid latex files, here called "old.tex" and "new.tex", finds
       significant differences between them (i.e., ignoring the number of white spaces and
       position of line breaks), and adds special commands to highlight the differences.  Where
       visual highlighting is not possible, e.g. for changes in the formatting, the differences
       are nevertheless marked up in the source.

       The program treats the preamble differently from the main document.  Differences between
       the preambles are found using line-based differencing (similarly to the Unix diff command,
       but ignoring white spaces).  A comment, ""%DIF >"" is appended to each added line, i.e. a
       line present in "new.tex" but not in "old.tex".  Discarded lines
        are deactivated by prepending ""%DIF <"". Changed blocks are preceded  by comment lines
       giving information about line numbers in the original files.  Where there are
       insignificant differences, the resulting file "diff.tex" will be similar to "new.tex".  At
       the end of the preamble, the definitions for latexdiff markup commands are inserted.  In
       differencing the main body of the text, latexdiff attempts to satisfy the following
       guidelines (in order of priority):

       1. If both "old.tex" and "new.tex" are valid LaTeX, then the resulting "diff.tex" should
          also be valid LateX. (NB If a few plain TeX commands are used within "old.tex" or
          "new.tex" then "diff.tex" is not guaranteed to work but usually will).

       2. Significant differences are determined on the level of individual words. All
          significant differences, including differences between comments should be clearly
          marked in the resulting source code "diff.tex".

       3. If a changed passage contains text or text-producing commands, then running "diff.tex"
          through LateX should produce output where added and discarded passages are highlighted.

       4. Where there are insignificant differences, e.g. in the positioning of line breaks,
          "diff.tex" should follow the formatting of "new.tex"

       For differencing the same algorithm as diff is used but words instead of lines are
       compared.  An attempt is made to recognize blocks which are completely changed such that
       they can be marked up as a unit.  Comments are differenced line by line but the number of
       spaces within comments is ignored. Commands including all their arguments are generally
       compared as one unit, i.e., no mark-up is inserted into the arguments of commands.
       However, for a selected number of commands (for example, "\caption" and all sectioning
       commands) the last argument is known to be text. This text is split into words and
       differenced just as ordinary text (use options to show and change the list of text
       commands, see below). As the algorithm has no detailed knowledge of LaTeX, it assumes all
       pairs of curly braces immediately following a command (i.e. a sequence of letters
       beginning with a backslash) are arguments for that command.  As a restriction to condition
       1 above it is thus necessary to surround all arguments with curly braces, and to not
       insert extraneous spaces.  For example, write

         \section{\textem{This is an emphasized section title}}

       and not

         \section {\textem{This is an emphasized section title}}

       or

         \section\textem{This is an emphasized section title}

       even though all varieties are the same to LaTeX (but see --allow-spaces option which
       allows the second variety).

       For environments whose content does not conform to standard LaTeX or where graphical
       markup does not make sense all markup commands can be removed by setting the PICTUREENV
       configuration variable, set by default to "picture" and "DIFnomarkup" environments; see
       --config option).  The latter environment ("DIFnomarkup") can be used to protect parts of
       the latex file where the markup results in illegal markup. You have to surround the
       offending passage in both the old and new file by "\begin{DIFnomarkup}" and
       "\end{DIFnomarkup}". You must define the environment in the preambles of both old and new
       documents. I prefer to define it as a null-environment,

       "\newenvironment{DIFnomarkup}{}{}"

       but the choice is yours.  Any markup within the environment will be removed, and generally
       everything within the environment will just be taken from the new file.

       It is also possible to difference files which do not have a preamble.
        In this case, the file is processed in the main document mode, but the definitions of the
       markup commands are not inserted.

       All markup commands inserted by latexdiff begin with ""\DIF"".  Added blocks containing
       words, commands or comments which are in "new.tex" but not in "old.tex" are marked by
       "\DIFaddbegin" and "\DIFaddend".  Discarded blocks are marked by "\DIFdelbegin" and
       "\DIFdelend".  Within added blocks all text is highlighted with "\DIFadd" like this:
       "\DIFadd{Added text block}" Selected `safe' commands can be contained in these text blocks
       as well (use options to show and change the list of safe commands, see below).  All other
       commands as well as braces "{" and "}" are never put within the scope of "\DIFadd".  Added
       comments are marked by prepending ""%DIF > "".

       Within deleted blocks text is highlighted with "\DIFdel".  Deleted comments are marked by
       prepending ""%DIF < "".  Non-safe command and curly braces within deleted blocks are
       commented out with ""%DIFDELCMD < "".

OPTIONS

   Preamble
       The following options determine the visual markup style by adding the appropriate command
       definitions to the preamble. See the end of this section for a description of available
       styles.

       --type=markupstyle or -t markupstyle
           Add code to preamble for selected markup style. This option defines "\DIFadd" and
           "\DIFdel" commands.  Available styles:

           "UNDERLINE CTRADITIONAL TRADITIONAL CFONT FONTSTRIKE INVISIBLE CHANGEBAR CCHANGEBAR
           CULINECHBAR CFONTCBHBAR BOLD"

           [ Default: "UNDERLINE" ]

       --subtype=markstyle or -s markstyle
           Add code to preamble for selected style for bracketing commands (e.g. to mark changes
           in  margin). This option defines "\DIFaddbegin", "\DIFaddend", "\DIFdelbegin" and
           "\DIFdelend" commands.  Available styles: "SAFE MARGIN COLOR DVIPSCOL  ZLABEL
           ONLYCHANGEDPAGE (LABEL)*"

           [ Default: "SAFE" ] * Subtype "LABEL" is deprecated

       --floattype=markstyle or -f markstyle
           Add code to preamble for selected style which replace standard marking and markup
           commands within floats (e.g., marginal remarks cause an error within floats so
           marginal marking can be disabled thus). This option defines all "\DIF...FL" commands.
           Available styles: "FLOATSAFE TRADITIONALSAFE IDENTICAL"

           [ Default: "FLOATSAFE" ]

       --encoding=enc or -e enc
           Specify encoding of old.tex and new.tex. Typical encodings are "ascii", "utf8",
           "latin1", "latin9".  A list of available encodings can be obtained by executing

           "perl -MEncode -e 'print join ("\n",Encode-"encodings( ":all" )) ;' >

           [Default encoding is utf8 unless the first few lines of the preamble contain an
           invocation "\usepackage[..]{inputenc}" in which case the encoding chosen by this
           command is asssumed. Note that ASCII (standard latex) is a subset of utf8]

       --preamble=file or -p file
           Insert file at end of preamble instead of generating preamble.  The preamble must
           define the following commands "\DIFaddbegin, \DIFaddend, \DIFadd{..},
           \DIFdelbegin,\DIFdelend,\DIFdel{..}," and varieties for use within floats
           "\DIFaddbeginFL, \DIFaddendFL, \DIFaddFL{..}, \DIFdelbeginFL, \DIFdelendFL,
           \DIFdelFL{..}" (If this option is set -t, -s, and -f options are ignored.)

       --packages=pkg1,pkg2,..
           Tell latexdiff that .tex file is processed with the packages in list loaded.  This is
           normally not necessary if the .tex file includes the preamble, as the preamble is
           automatically scanned for "\usepackage" commands.  Use of the --packages option
           disables automatic scanning, so if for any reason package specific parsing needs to be
           switched off, use --packages=none.  The following packages trigger special behaviour:

           "amsmath"
                   Configuration variable MATHARRREPL is set to "align*" (Default: "eqnarray*").
                   (Note that many of the amsmath array environments are already recognised by
                   default as such)

           "endfloat"
                   Ensure that "\begin{figure}" and "\end{figure}" always appear by themselves on
                   a line.

           "hyperref"
                   Change name of "\DIFadd" and "\DIFdel" commands to "\DIFaddtex" and
                   "\DIFdeltex" and define new "\DIFadd" and "\DIFdel" commands, which provide a
                   wrapper for these commands, using them for the text but not for the link
                   defining command (where any markup would cause errors).

           "apacite"
                   Redefine the commands recognised as citation commands.

           "siunitx"
                   Treat "\SI" as equivalent to citation commands (i.e. protect with "\mbox" if
                   markup style uses ulem package.

           "cleveref"
                   Treat "\cref,\Cref", etc as equivalent to citation commands (i.e. protect with
                   "\mbox" if markup style uses ulem package.

           "glossaries"
                   Define most of the glossaries commands as safe, protecting them with \mbox'es
                   where needed

           "mhchem"
                   Treat "\ce" as a safe command, i.e. it will be highlighted (note that "\cee"
                   will not be highlighted in equations as this leads to processing errors)

           "chemformula" or "chemmacros"
                   Treat "\ch" as a safe command outside equations, i.e. it will be highlighted
                   (note that "\ch" will not be highlighted in equations as this leads to
                   processing errors)

           [ Default: scan the preamble for "\usepackage" commands to determine
             loaded packages. ]

       --show-preamble
           Print generated or included preamble commands to stdout.

   Configuration
       --exclude-safecmd=exclude-file or -A exclude-file or  --exclude-safecmd="cmd1,cmd2,..."
       --replace-safecmd=replace-file
       --append-safecmd=append-file or -a append-file or --append-safecmd="cmd1,cmd2,..."
           Exclude from, replace or append to the list of regular expressions (RegEx) matching
           commands which are safe to use within the scope of a "\DIFadd" or "\DIFdel" command.
           The file must contain one Perl-RegEx per line (Comment lines beginning with # or % are
           ignored).  Note that the RegEx needs to match the whole of the token, i.e., /^regex$/
           is implied and that the initial "\" of the command is not included.  The
           --exclude-safecmd and --append-safecmd options can be combined with the
           ---replace-safecmd option and can be used repeatedly to add cumulatively to the lists.
            --exclude-safecmd and --append-safecmd can also take a comma separated list as input.
           If a comma for one of the regex is required, escape it thus "\,". In most cases it
           will be necessary to protect the comma-separated list from the shell by putting it in
           quotation marks.

       --exclude-textcmd=exclude-file or -X exclude-file or --exclude-textcmd="cmd1,cmd2,..."
       --replace-textcmd=replace-file
       --append-textcmd=append-file or -x append-file or --append-textcmd="cmd1,cmd2,..."
           Exclude from, replace or append to the list of regular expressions matching commands
           whose last argument is text.  See entry for --exclude-safecmd directly above for
           further details.

       --replace-context1cmd=replace-file
       --append-context1cmd=append-file or =item --append-context1cmd="cmd1,cmd2,..."
           Replace or append to the list of regex matching commands whose last argument is text
           but which require a particular context to work, e.g. \caption will only work within a
           figure or table.  These commands behave like text commands, except when they occur in
           a deleted section, when they are disabled, but their argument is shown as deleted
           text.

       --replace-context2cmd=replace-file
       --append-context2cmd=append-file or =item --append-context2cmd="cmd1,cmd2,..."
           As corresponding commands for context1.  The only difference is that context2 commands
           are completely disabled in deleted sections, including their arguments.

       --exclude-mboxsafecmd=exclude-file or --exclude-mboxsafecmd="cmd1,cmd2,..."
       --append-mboxsafecmd=append-file or --append-mboxsafecmd="cmd1,cmd2,..."
           Define safe commands, which additionally need to be protected by encapsulating in an
           \\mbox{..}. This is sometimes needed to get around incompatibilities between external
           packages and the ulem package, which is  used for highlighting in the default style
           UNDERLINE as well as CULINECHBAR CFONTSTRIKE

       --config var1=val1,var2=val2,... or -c var1=val1,..
       -c configfile
           Set configuration variables.  The option can be repeated to set different variables
           (as an alternative to the comma-separated list).  Available variables (see below for
           further explanations):

           "ARRENV" (RegEx)

           "COUNTERCMD" (RegEx)

           "FLOATENV" (RegEx)

           "ITEMCMD" (RegEx)

           "LISTENV"  (RegEx)

           "MATHARRENV" (RegEx)

           "MATHARRREPL" (String)

           "MATHENV" (RegEx)

           "MATHREPL" (String)

           "MINWORDSBLOCK" (integer)

           "PICTUREENV" (RegEx)

       --show-safecmd
           Print list of RegEx matching and excluding safe commands.

       --show-textcmd
           Print list of RegEx matching and excluding commands with text argument.

       --show-config
           Show values of configuration variables.

       --show-all
           Combine all --show commands.

           NB For all --show commands, no "old.tex" or "new.tex" file needs to be specified, and
           no differencing takes place.

   Other configuration options:
       --allow-spaces
           Allow spaces between bracketed or braced arguments to commands.  Note that this option
           might have undesirable side effects (unrelated scope might get lumpeded with preceding
           commands) so should only be used if the default produces erroneous results.  (Default
           requires arguments to directly follow each other without intervening spaces).

       --math-markup=level
           Determine granularity of markup in displayed math environments: Possible values for
           level are (both numerical and text labels are acceptable):

           "off" or 0: suppress markup for math environments.  Deleted equations will not appear
           in diff file. This mode can be used if all the other modes cause invalid latex code.

           "whole" or 1: Differencing on the level of whole equations. Even trivial changes to
           equations cause the whole equation to be marked changed.  This mode can be used if
           processing in coarse or fine mode results in invalid latex code.

           "coarse" or 2: Detect changes within equations marked up with a coarse granularity;
           changes in equation type (e.g.displaymath to equation) appear as a change to the
           complete equation. This mode is recommended for situations where the content and order
           of some equations are still being changed. [Default]

           "fine" or 3: Detect small change in equations and mark up at fine granularity.  This
           mode is most suitable, if only minor changes to equations are expected, e.g.
           correction of typos.

       --disable-citation-markup or --disable-auto-mbox
           Suppress citation markup and markup of other vulnerable commands in styles using ulem
           (UNDERLINE,FONTSTRIKE, CULINECHBAR) (the two options are identical and are simply
           aliases)

       --enable-citation-markup or --enforce-auto-mbox
           Protect citation commands and other vulnerable commands in changed sections with
           "\mbox" command, i.e. use default behaviour for ulem package for other packages (the
           two options are identical and are simply aliases)

   Miscellaneous
       --verbose or -V
           Output various status information to stderr during processing.  Default is to work
           silently.

       --driver=type
           Choose driver for changebar package (only relevant for styles using
              changebar: CCHANGEBAR CFONTCHBAR CULINECHBAR CHANGEBAR). Possible drivers are
           listed in changebar manual, e.g. pdftex,dvips,dvitops
             [Default: dvips]

       --ignore-warnings
           Suppress warnings about inconsistencies in length between input and parsed strings and
           missing characters.  These warning messages are often related to non-standard latex or
           latex constructions with a syntax unknown to "latexdiff" but the resulting difference
           argument is often fully functional anyway, particularly if the non-standard latex only
           occurs in parts of the text which have not changed.

       --label=label or -L label
           Sets the labels used to describe the old and new files.  The first use of this option
           sets the label describing the old file and the second use of the option sets the label
           for the new file, i.e. set both labels like this "-L labelold -L labelnew".  [Default:
           use the filename and modification dates for the label]

       --no-label
           Suppress inclusion of old and new file names as comment in output file

       --visble-label
           Include old and new filenames (or labels set with "--label" option) as visible output.

       --flatten
           Replace "\input" and "\include" commands within body by the content of the files in
           their argument.  If "\includeonly" is present in the preamble, only those files are
           expanded into the document. However, no recursion is done, i.e. "\input" and
           "\include" commands within included sections are not expanded.  The included files are
           assumed to
            be located in the same directories as the old and new master files, respectively,
           making it possible to organise files into old and new directories.  --flatten is
           applied recursively, so inputted files can contain further "\input" statements.

           Use of this option might result in prohibitive processing times for larger documents,
           and the resulting difference document no longer reflects the structure of the input
           documents.

       --help or -h
           Show help text

       --version
           Show version number

   Predefined styles
   Major types
       The major type determine the markup of plain text and some selected latex commands outside
       floats by defining the markup commands "\DIFadd{...}" and "\DIFdel{...}" .

       "UNDERLINE"
                 Added text is wavy-underlined and blue, discarded text is struck out and red
                 (Requires color and ulem packages).  Overstriking does not work in displayed
                 math equations such that deleted parts of equation are underlined, not struck
                 out (this is a shortcoming inherent to the ulem package).

       "CTRADITIONAL"
                 Added text is blue and set in sans-serif, and a red footnote is created for each
                 discarded piece of text. (Requires color package)

       "TRADITIONAL"
                 Like "CTRADITIONAL" but without the use of color.

       "CFONT"   Added text is blue and set in sans-serif, and discarded text is red and very
                 small size.

       "FONTSTRIKE"
                 Added tex is set in sans-serif, discarded text small and struck out

       "CCHANGEBAR"
                 Added text is blue, and discarded text is red.  Additionally, the changed text
                 is marked with a bar in the margin (Requires color and changebar packages).

       "CFONTCHBAR"
                 Like "CFONT" but with additional changebars (Requires color and changebar
                 packages).

       "CULINECHBAR"
                 Like "UNDERLINE" but with additional changebars (Requires color, ulem and
                 changebar packages).

       "CHANGEBAR"
                 No mark up of text, but mark margins with changebars (Requires changebar
                 package).

       "INVISIBLE"
                 No visible markup (but generic markup commands will still be inserted.

       "BOLD"    Added text is set in bold face, discarded is not shown.

   Subtypes
       The subtype defines the commands that are inserted at the begin and end of added or
       discarded blocks, irrespectively of whether these blocks contain text or commands (Defined
       commands: "\DIFaddbegin, \DIFaddend, \DIFdelbegin, \DIFdelend")

       "SAFE"    No additional markup (Recommended choice)

       "MARGIN"  Mark beginning and end of changed blocks with symbols in the margin nearby
                 (using the standard "\marginpar" command - note that this sometimes moves
                 somewhat from the intended position.

       "COLOR"   An alternative way of marking added passages in blue, and deleted ones in red.
                 (It is recommeneded to use instead the main types to effect colored markup,
                 although in some cases coloring with dvipscol can be more complete, for example
                 with citation commands).

       "DVIPSCOL"
                 An alternative way of marking added passages in blue, and deleted ones in red.
                 Note that "DVIPSCOL" only works with the dvips converter, e.g. not pdflatex.
                 (it is recommeneded to use instead the main types to effect colored markup,
                 although in some cases coloring with dvipscol can be more complete).

       "ZLABEL"  can be used to highlight only changed pages, but requires post-processing. It is
                 recommend to not call this option manually but use "latexdiff-vc" with
                 "--only-changes" option. Alternatively, use the script given within preamble of
                 diff files made using this style.

       "ONLYCHANGEDPAGE"
                 also highlights changed pages, without the need for post-processing, but might
                 not work reliably if there is floating material (figures, tables).

       "LABEL"   is similar to "ZLABEL", but does not need the zref package and works less
                 reliably (deprecated).

   Float Types
       Some of the markup used in the main text might cause problems when used within floats
       (e.g. figures or tables).  For this reason alternative versions of all markup commands are
       used within floats. The float type defines these alternative commands.

       "FLOATSAFE"
                 Use identical markup for text as in the main body, but set all commands marking
                 the begin and end of changed blocks to null-commands.  You have to choose this
                 float type if your subtype is "MARGIN" as "\marginpar" does not work properly
                 within floats.

       "TRADITIONALSAFE"
                 Mark additions the same way as in the main text.  Deleted environments are
                 marked by angular brackets \[ and \] and the deleted text is set in scriptscript
                 size. This float type should always be used with the "TRADITIONAL" and
                 "CTRADITIONAL" markup types as the \footnote command does not work properly in
                 floating environments.

       "IDENTICAL"
                 Make no difference between the main text and floats.

   Configuration Variables
       "ARRENV"  If a match to "ARRENV" is found within an inline math environment within a
                 deleted or added block, then the inlined math is surrounded by "\mbox{"..."}".
                 This is necessary as underlining does not work within inlined array
                 environments.

                 [ Default: "ARRENV"="(?:array|[pbvBV]matrix)"

       "COUNTERCMD"
                 If a command in a deleted block which is also in the textcmd list matches
                 "COUNTERCMD" then an additional command "\addtocounter{"cntcmd"}{-1}", where
                 cntcmd is the matching command, is appended in the diff file such that the
                 numbering in the diff file remains synchronized with the numbering in the new
                 file.

                 [ Default: "COUNTERCMD"="(?:footnote|part|section|subsection" ...

                 "|subsubsection|paragraph|subparagraph)"  ]

       "FLOATENV"
                 Environments whose name matches the regular expression in "FLOATENV" are
                 considered floats.  Within these environments, the latexdiff markup commands are
                 replaced by their FL variaties.

                 [ Default: "(?:figure|table|plate)[\w\d*@]*" ]

       "ITEMCMD" Commands representing new item line with list environments.

                 [ Default: \"item" ]

       "LISTENV" Environments whose name matches the regular expression in "LISTENV" are list
                 environments.

                 [ Default: "(?:itemize|enumerate|description)" ]

       "MATHENV","MATHREPL"
                 If both \begin and \end for a math environment (environment name matching
                 "MATHENV" or \[ and \]) are within the same deleted block, they are replaced by
                 a \begin and \end commands for "MATHREPL" rather than being commented out.

                 [ Default: "MATHENV"="(?:displaymath|equation)" , "MATHREPL"="displaymath" ]

       "MATHARRENV","MATHARRREPL"
                 as "MATHENV","MATHREPL" but for equation arrays

                 [ Default: "MATHARRENV"="eqnarray\*?" , "MATHREPL"="eqnarray" ]

       "MINWORDSBLOCK"
                 Minimum number of tokens required to form an independent block. This value is
                 used in the algorithm to detect changes of complete blocks by merging identical
                 text parts of less than "MINWORDSBLOCK" to the preceding added and discarded
                 parts.

                 [ Default: 3 ]

       "PICTUREENV"
                 Within environments whose name matches the regular expression in "PICTUREENV"
                 all latexdiff markup is removed (in pathologic cases this might lead to
                 inconsistent markup but this situation should be rare).

                 [ Default: "(?:picture|DIFnomarkup)[\w\d*@]*" ]

COMMON PROBLEMS AND FAQ

       Citations result in overfull boxes
                 There is an incompatibility between the "ulem" package, which "latexdiff" uses
                 for underlining and striking out in the UNDERLINE style, the default style, and
                 the way citations are generated. In order to be able to mark up citations
                 properly, they are enclosed with an "\mbox" command. As mboxes cannot be broken
                 across lines, this procedure frequently results in overfull boxes, possibly
                 obscuring the content as it extends beyond the right margin.  The same occurs
                 for some other packages (e.g., siunitx). If this is a problem, you have two
                 possibilities.

                 1. Use "CFONT" type markup (option "-t CFONT"): If this markup is chosen, then
                 changed citations are no longer marked up with the wavy line (additions) or
                 struck out (deletions), but are still highlighted in the appropriate color, and
                 deleted text is shown with a different font. Other styles not using the "ulem"
                 package will also work.

                 2. Choose option "--disable-citation-markup" which turns off the marking up of
                 citations: deleted citations are no longer shown, and added citations are shown
                 without markup. (This was the default behaviour of latexdiff at versions 0.6 and
                 older)

                 For custom packages you can define the commands which need to be protected by
                 "\mbox" with "--append-mboxsafecmd" and "--excludemboxsafecmd" options (submit
                 your lists of command as feature request at github page to set the default
                 behaviour of future versions, see section 6)

       Changes in complicated mathematical equations result in latex processing errors
                 Try options "--math-markup=whole".   If even that fails, you can turn off mark
                 up for equations with "--math-markup=off".

       How can I just show the pages where changes had been made
                 Use options -"-s ZLABEL"  (some postprocessing required) or "-s
                 ONLYCHANGEDPAGE". "latexdiff-vc --ps|--pdf" with "--only-changes" option takes
                 care of the post-processing for you (requires zref package to be installed).

BUGS

       Option allow-spaces not implemented entirely consistently. It breaks the rules that number
       and type of white space does not matter, as different numbers of inter-argument spaces are
       treated as significant.

       Please submit bug reports using the issue tracker of the github repository page
       https://github.com/ftilmann/latexdiff.git, or send them to tilmann -- AT --
       gfz-potsdam.de.  Include the version number of latexdiff (from comments at the top of the
       source or use --version).  If you come across latex files that are error-free and conform
       to the specifications set out above, and whose differencing still does not result in
       error-free latex, please send me those files, ideally edited to only contain the offending
       passage as long as that still reproduces the problem. If your file relies on non-standard
       class files, you must include those.  I will not look at examples where I have trouble to
       latex the original files.

SEE ALSO

       latexrevise, latexdiff-vc

PORTABILITY

       latexdiff does not make use of external commands and thus should run on any platform
       supporting Perl 5.6 or higher.  If files with encodings other than ASCII or UTF-8 are
       processed, Perl 5.8 or higher is required.

       The standard version of latexdiff requires installation of the Perl package
       "Algorithm::Diff" (available from www.cpan.org -
       http://search.cpan.org/~nedkonz/Algorithm-Diff-1.15) but a stand-alone version, latexdiff-
       so, which has this package inlined, is available, too.  latexdiff-fast requires the diff
       command to be present.

AUTHOR

       Version 1.1.1 Copyright (C) 2004-2015 Frederik Tilmann

       This program is free software; you can redistribute it and/or modify it under the terms of
       the GNU General Public License Version 3

       Contributors of fixes and additions: V. Kuhlmann, J. Paisley, N. Becker, T. Doerges, K.
       Huebner, T. Connors, Sebastian Gouezel and many others.  Thanks to the many people who
       sent in bug reports, feature suggestions, and other feedback.