DIFF3(1) | General Commands Manual | DIFF3(1) |
diff3
— 3-way
differential file comparison
diff3 |
[-3AaEeimTXx ]
[--diff-program program]
[--strip-trailing-cr ] [-L
| --label label1]
[-L | --label
label2] [-L |
--label label3]
file1 file2 file3 |
diff3 |
[--help ]
[--version ] |
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
,
--easy-only
-A
--show-all
-a
,
--text
-E
,
--show-overlap
-X
-e
and -x
,
respectively, but treat overlapping changes (i.e., changes that would be
noted with ==== in the normal listing) differently. The overlapping lines
from both files will be inserted by the edit script, bracketed by
"<<<<<<" and
">>>>>>" lines.-e
,
--ed
-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.--help
-i
-L
,
--label
-m,
--merge
-T,
--initial-tab
-x,
--overlap-only
--diff-program
program--strip-trailing-cr
--version
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. Applying 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.
====
A diff3
command appeared in
Version 7 AT&T UNIX.
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.
June 23, 2022 | macOS 14.6 |