Provided by: fhist_1.18-2build1_amd64 bug


       fcomp - file compare


       fcomp [ option...  ] filename1 filename2

       fcomp -Help

       fcomp -VERSion


       The  fcomp  program  is  used  to compare text files, similar to the diff(1) program.  Its
       advantage is that it always produces minimal differences, and so will never mis‐sync  when
       comparing  files.   Its disadvantage is that it runs slower due to the extra work required
       to produce optimal differences.  However, for files differing by less than a few  thousand
       lines,  its performance is adequate.  The algorithms used by this utility are also used by
       the fhist(1) program in order to produce the edit history.

       To compare file old to file new, the command:
              fcomp old new
       would be used.  This gives the differences involved in converting from file  old  to  file
       new.   This  is analogous to the use of the cp(1) command.  Either the old or new file may
       be a directory, in which case the comparison is done to the file in the directory with the
       same name as the other file.  An error is given if old and new are both directories.


       The following options are understood:

       -BINary This  option  may be used to compare binary files on a byte‐for‐byte basis.  (Each
               byte is treated as a “line” by the  algorithm.)   Byte  values  are  displayed  in
               hexadecimal,  as  are  the  addresses.   Note:  this is different behaviour to the
               fhist(1) option of the same name.

               This option may be used to avoid  comparing  binary  files.   A  warnign  will  be
               prointed  on  the  standard  error,  but  the  program will report success without
               printing andy other output.

               Ignore blank lines in the input files.

       -Context number
               This specifies the number of lines of "context" which is  displayed.   This  shows
               the  specified  number  of  lines before and after the actual lines being changed.
               This is useful to locate and identify the line which is  actually  being  changed,
               when there are many identical copies of the line in the file.

               Output an edit script which is machine readable.

       -Failures number
               This  stops  the comparison if the number of changes exceeds the specified number.
               Each change is a delete or insert of a single line.  This is useful when  you  are
               not  interested  in the results when the files are totally different.  Another use
               is a quick check to see if two files are identical, by using a value of zero.

               Give some help on how to use the fcomp program.

       -Join number
               This merges together lines which have changed, if they are separated by up to  the
               specified number of unchanged lines.  This makes a change look bigger, but reduces
               the "choppiness" of the output by showing fewer regions being  changed.   This  is
               particularly  effective  to  suppress worthless matchings of single blank lines or
               comment beginning and ending lines.  A useful value for this option is 3 or so.

               Output matching lines, rather then changed lines.

               This outputs the line numbers at the left edge of the output.  This isn't normally
               needed,  since  the  line  numbers are displayed in the comment line preceding the
               lines being displayed.  Not outputting the line numbers prevents the terminal from
               needlessly scrolling for long lines.

       -Output filename
               Send the output to this file, rather than the standard output.

               Output only a quick summary of changes needed.

               This  option  ignores  differences in the number of spaces in the two lines.  That
               is, two or more adjacent spaces are handled as a  single  space.   Spaces  at  the
               beginning or end of a line are totally ignored.

               Uppercase lines before comparing.

               Show what version of fcomp is running.

               This outputs all of both files together, showing what happened to each line of the
               first file in order to change to the line in the second file.  This output  is  in
               "change  bar" format, where inserted lines begin with |+, deleted lines begin with
               |−, and unchanged lines begin with spaces.  The presence of the vertical bar makes
               it easy to search for the changed lines.

       All  options may be abbreviated; the abbreviation is documented as the upper case letters,
       all lower case letters and  underscores  (_)  are  optional.   You  must  use  consecutive
       sequences of optional letters.

       All  options  are  case  insensitive,  you  may type them in upper case or lower case or a
       combination of both, case is not important.

       For example: the arguments "-help, "-HELP" and "-h" are all interpreted to mean the  -Help
       option.   The  argument  "-hlp"  will  not  be  understood,  because  consecutive optional
       characters were not supplied.

       Options and other command line arguments may be mixed arbitrarily on the command line.

       The GNU long option names are understood.  Since all option names for fcomp are long, this
       means ignoring the extra leading '-'.  The "-option=value" convention is also understood.


       As  a  convenience,  if  a pathname begins with a period and a environment variable exists
       with that name, then the value of the environment variable will  be  used  as  the  actual
       pathname.    For   example,   if   a   environment   variable   of   .FOO  has  the  value, then the command
              fcomp -o .FOO
       is actually equivilant to the command
              fcomp -o
       If you want to prevent the expansion of a pathname which begins with a  period,  then  you
       can use an alternate form for the pathname, as in:
              fcomp -o ./.FOO


       In  general, fcomp can handle all text files you throw at it, even international text with
       unusual encodings.  However, fcomp is unable to cope elegantly with  files  which  contain
       the NUL character.

       The  fcomp(1)  program  simply  prints  a warning, and continues, you need to know that it
       converts NUL characters into an 0x80 value before performing the comparison.

       The fmerge(1) program also converts the NUL character to an  0x80  value  before  merging,
       after a warning, and any output file will contain this value, rather than the original NUL

       The fhist(1) program, however, generates a fatal error if  any  input  file  contains  NUL
       characters.   This  is intended to protect your source files for unintentional corruption.
       Use -BINary for files which absolutely must contain NUL characters.


       The fcomp program will exit with a status of 1 on any error.  The fcomp program will  only
       exit with a status of 0 if there are no errors.


       This program is based on the algorithm in
              An  O(ND)  Difference  Algorithm  and  Its  Variations,  Eugene  W. Myers, TR 85‐6,
              10‐April‐1985, Department of Computer Science, The University of  Arizona,  Tuscon,
              Arizona 85721.
       See also:
              A  File  Comparison Program, Webb Miller and Eugene W. Myers, Software Practice and
              Experience, Volume 15, No. 11, November 1985.


       fcomp version 1.18.D001
       Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997,  1998,  1999,  2000,  2001,  2002,
       2003, 2004, 2005, 2006, 2008, 2009 Peter Miller;

       This program is derived from a work
       Copyright (C) 1990 David I. Bell.

       This program 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.

       This  program 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 <>.


       Peter Miller       Web:
       /\/\*           E‐Mail:

       David I. Bell      Web: