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MERGE(1) General Commands Manual MERGE(1)


merge - three-way file merge


merge [ options ] file1 file2 file3


merge incorporates all changes that lead from file2 to file3 into file1. The result ordinarily goes into file1. merge is useful for combining separate changes to an original. Suppose file2 is the original, and both file1 and file3 are modifications of file2. Then merge combines both changes.

A conflict occurs if both file1 and file3 have changes in a common segment of lines. If a conflict is found, merge normally outputs a warning and brackets the conflict with <<<<<<< and >>>>>>> lines. A typical conflict will look like this:

<<<<<<< file A
lines in file A
lines in file B
>>>>>>> file B

If there are conflicts, the user should edit the result and delete one of the alternatives.


Output conflicts using the -A style of diff3(1), if supported by diff3. This merges all changes leading from file2 to file3 into file1, and generates the most verbose output.
These options specify conflict styles that generate less information than -A. See diff3(1) for details. The default is -E. With -e, merge does not warn about conflicts.
This option may be given up to three times, and specifies labels to be used in place of the corresponding file names in conflict reports. That is, merge -L x -L y -L z a b c generates output that looks like it came from files x, y and z instead of from files a, b and c.
Send results to standard output instead of overwriting file1.
Quiet; do not warn about conflicts.
Print RCS's version number.


Exit status is 0 for no conflicts, 1 for some conflicts, 2 for trouble.


Author: Walter F. Tichy.
Manual Page Revision: 5.10.1; Release Date: 2022-02-19.
Copyright © 2010-2022 Thien-Thi Nguyen.
Copyright © 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert.
Copyright © 1982, 1988, 1989 Walter F. Tichy.


diff3(1), diff(1), rcsmerge(1), co(1).

The full documentation for RCS is maintained as a Texinfo manual. If the info(1) and RCS programs are properly installed at your site, the command

info rcs

should give you access to the complete manual. Additionally, the RCS homepage:

has news and links to the latest release, development site, etc.


It normally does not make sense to merge binary files as if they were text, but merge tries to do it anyway.

2022-02-19 GNU RCS 5.10.1