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


       gendiff <directory> <diff-extension>


       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 changes.

       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 (somefile.cpp).

       After editing all the files you need to edit in this fashion, enter 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.


       diff(1), patch(1)


       Marc Ewing <>