gendiff(1) — Linux manual page


GENDIFF(1)                                                    GENDIFF(1)

NAME         top

       gendiff - utility to aid in error-free diff file generation

SYNOPSIS         top

       gendiff <directory> <diff-extension>

DESCRIPTION         top

       gendiff is a rather simple script which aids in generating a diff
       file from a single directory.  It takes a directory name and a
       "diff-extension" as its only arguments.  The diff extension
       should be a unique sequence of characters added to the end of all
       original, unmodified files.  The output of the program is a diff
       file which may be applied with the patch program to recreate the

       The usual sequence of events for creating a diff is to create two
       identical directories, make changes in one directory, and then
       use the diff utility to create a list of differences between the
       two.  Using gendiff eliminates the need for the extra, original
       and unmodified directory copy.  Instead, only the individual
       files that are modified need to be saved.

       Before editing a file, copy the file, appending the extension you
       have chosen to the filename.  I.e.  if you were going to edit
       somefile.cpp and have chosen the extension "fix", copy it to
       somefile.cpp.fix before editing it.  Then edit the first copy

       After editing all the files you need to edit in this fashion, en‐
       ter the directory one level above where your source code resides,
       and then type

                  $ gendiff somedirectory .fix > mydiff-fix.patch

       You should redirect the output to a file (as illustrated) unless
       you want to see the results on stdout.

SEE ALSO         top

       diff(1), patch(1)

AUTHOR         top

              Marc Ewing <>

COLOPHON         top

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                             Mon Jan 10 2000                  GENDIFF(1)

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