combinediff

COMBINEDIFF(1)						       COMBINEDIFF(1)



NAME
       combinediff  -  create a cumulative unified patch from two incremental
       patches

SYNOPSIS
       combinediff [-p n] [-U n] [-d PAT] [-Bbiqwz] [--interpolate |
		   --combine] diff1 diff2

       combinediff {--help | --version}


DESCRIPTION
       combinediff  creates  a	unified	 diff  that  expresses the sum of two
       diffs. The diff files must be listed in the order that they are to  be
       applied. For best results, the diffs must have at least three lines of
       context.


       Since combinediff 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 be in strict incremental or-
       der. In other words, the second patch must be relative to the state of
       the original set of files after the first patch was applied.


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


OPTIONS
       -p n   When comparing filenames, ignore the first  n  pathname  compo-
	      nents  from  both patches. (This is similar to the -p option to
	      GNU patch(1).)


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


       -U 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
	      Don’t  display  any context on files that match the shell wild-
	      card 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     Consider upper- and lower-case to be the same.


       -w     Ignore whitespace changes in patches.


       -b     Ignore changes in the amount of whitespace.


       -B     Ignore changes whose lines are all blank.


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


       --interpolate
	      Run as ‘‘interdiff’’. See	 interdiff(1)  for  more  information
	      about how the behaviour is altered in this mode.


       --combine
	      Run as ‘‘combinediff’’. This is the default.


       --help Display a short usage message.


       --version
	      Display the version number of combinediff.


BUGS
       The  -U	option is a bit erratic: it can control the amount of context
       displayed for files that are modified in both  patches,	but  not  for
       files that only appear in one patch (which appear with the same amount
       of context in the output as in the input).


SEE ALSO
       interdiff(1)


AUTHOR
       Tim Waugh <twaugh@redhat.com>.



patchutils			  7 Jul 2003		       COMBINEDIFF(1)