interdiff(1)

NAME

   interdiff - show differences between two diff files

SYNOPSIS

   interdiff [[-p n] | [--strip-match=n]] [[-U n] | [--unified=n]]
             [[-d PAT] | [--drop-context=PAT]] [[-q] | [--quiet]] [[-z] |
             [--decompress]] [[-b] | [--ignore-space-change]] [[-B] |
             [--ignore-blank-lines]] [[-i] | [--ignore-case]] [[-w] |
             [--ignore-all-space]] [[--interpolate] | [--combine] |
             [--flip]] [--no-revert-omitted] diff1 diff2

   interdiff {[--help] | [--version]}

DESCRIPTION

   interdiff creates a unified format diff that expresses the difference
   between two diffs. The diffs must both be relative to the same files.
   For best results, the diffs must have at least three lines of context.

   To reverse a patch, use /dev/null for diff2.

   To reduce the amount of context in a patch, use:

       interdiff -U1 /dev/null patchfile

   Since interdiff doesn't have the advantage of being able to look at the
   files that are to be modified, it has stricter requirements on the
   input format than patch(1) does. The output of GNU diff will be okay,
   even with extensions, but if you intend to use a hand-edited patch it
   might be wise to clean up the offsets and counts using recountdiff(1)
   first.

   Note, however, that the two patches must both be relative to the
   versions of the same original set of files.

   The diffs may be in context format. The output, however, will be in
   unified format.

OPTIONS

   -h
       Ignored, for compatibility with older versions of interdiff. This
       option will go away soon.

   -p n, --strip-match=n
       When comparing filenames, ignore the first n pathname components
       from both patches. (This is similar to the -p option to GNU
       patch(1).)

   -q, --quiet
       Quieter output. Don't emit rationale lines at the beginning of each
       patch.

   -U n, --unified=n
       Attempt to display n lines of context (requires at least n lines of
       context in both input files). (This is similar to the -U option to
       GNU diff(1).)

   -d PATTERN, --drop-context=PATTERN
       Don't display any context on files that match the shell wildcard
       PATTERN. This option can be given multiple times.

       Note that the interpretation of the shell wildcard pattern does not
       count slash characters or periods as special (in other words, no
       flags are given to fnmatch). This is so that "*/basename"-type
       patterns can be given without limiting the number of pathname
       components.

   -i, --ignore-case
       Consider upper- and lower-case to be the same.

   -w, --ignore-all-space
       Ignore whitespace changes in patches.

   -b, --ignore-space-change
       Ignore changes in the amount of whitespace.

   -B, --ignore-blank-lines
       Ignore changes whose lines are all blank.

   -z, --decompress
       Decompress files with extensions .gz and .bz2.

   --interpolate
       Run as "interdiff". This is the default.

   --combine
       Run as "combinediff". See combinediff(1) for more information about
       how the behaviour is altered in this mode.

   --no-revert-omitted
       (For interpolation mode only) When a file is changed by the first
       patch but not by the second, don't revert that change.

   --help
       Display a short usage message.

   --version
       Display the version number of interdiff.

EXAMPLES

   Basic usage:

       interdiff -z 3.2pre1.patch.gz 3.2pre2.patch.gz

   Reversing a patch:

       interdiff patch /dev/null

   Reversing part of a patch (and ignoring the rest):

       filterdiff -i file.c patchfile | \
         interdiff /dev/stdin /dev/null

BUGS

   There are currently no known bugs in interdiff; but there are some
   caveats. If you find a bug, please report it (along with a minimal test
   case) to Tim Waugh <twaugh@redhat.com>.

   There are some sets of patches in which there is just not enough
   information to produce a proper interdiff. In this case, the strategy
   employed is to revert the original patch and apply the new patch. This,
   unfortunately, means that interdiffs are not guaranteed to be
   reversible.

SEE ALSO

   combinediff(1)

AUTHORS

   Tim Waugh <twaugh@redhat.com>
       Package maintainer

   Michael K. Johnson <johnsonm@redhat.com>
       Original man page contributor

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Free and Open Source Software