DIFF3(1) BSD Reference Manual DIFF3(1)NAMEdiff3 - 3-way differential file comparison
SYNOPSISdiff3 [-3aEeXx] file1 file2 file3
DESCRIPTION
The diff3 utility compares the contents of three different versions of a
file, file1, file2 and file3, writing the result to the standard output.
The options describe different methods of merging and purging the
separate versions into a new file. diff3 is used by rcs(1) to merge
specific versions or create new versions.
The options are as follows:
-3 Produces an output script suitable for ed(1) with changes specif-
ic only to file3.
-a Treat all files as ASCII.
-E, -X Similar to -e and -x, respectively, but treat overlapping changes
(i.e., changes that would be noted with ==== in the normal list-
ing) differently. The overlapping lines from both files will be
inserted by the edit script, bracketed by "<<<<<<" and ">>>>>>"
lines.
-e Produces output in a form suitable as an input script for the
ed(1) utility. The script may then be used to merge differences
common between all three files and differences specific to file1
and file3. In other words, the -e option ignores differences
specific to file1 and file2, and those specific to file2 and
file3. It is useful for backing out changes specific to file2
only.
-x Produces an output script suitable for ed(1) with changes specif-
ic only to all three versions.
The -E option is used by RCS merge(1) to ensure that overlapping changes
in the merged files are preserved and brought to someone's attention.
For example, suppose lines 7-8 are changed in both file1 and file2. Ap-
plying the edit script generated by the command
$ diff3-E file1 file2 file3
to file1 results in the file:
lines 1-6
of file1
<<<<<<< file1
lines 7-8
of file1
=======
lines 7-8
of file3
>>>>>>> file3
rest of file1
The default output of diff3 makes notation of the differences between all
files, and those differences specific to each pair of files. The changes
are described by the commands necessary for ed(1) to create the desired
target from the different versions. See diff(1) for a description of the
commands.
==== The lines beneath this notation are ranges of lines which are dif-
ferent between all files.
====n The lines beneath this notation are ranges of lines which are ex-
clusively different in file n.
ENVIRONMENT
TMPDIR If the environment variable TMPDIR exists, diff3 will use the
directory specified by TMPDIR as the temporary directory.
FILES
/tmp/d3a.XXXXXXXXXX temporary file
/tmp/d3b.XXXXXXXXXX temporary file
/usr/libexec/diff3prog the actual executable
SEE ALSOdiff(1), ed(1), merge(1), rcs(1), sdiff(1)HISTORY
A diff3 command appeared in Version 7 AT&T UNIX.
BUGS
The -e option cannot catch and change lines which have '.' as the first
and only character on the line. The resulting script will fail on that
line as '.' is an ed(1) editing command.
MirOS BSD #10-current April 18, 1994 1
