Pathnames matching an RCS suffix denote RCS files; all others denote working files. Names are paired as explained in ci(1).

At least one revision must be specified with one of the options described below, usually -r. At most two revisions may be specified. If only one revision is specified, the latest revision on the default branch (normally the highest branch on the trunk) is assumed for the second revision. Revisions may be specified numerically or symbolically.

rcsmerge prints a warning if there are overlaps, and delimits the overlapping regions as explained in merge(1). The command is useful for incorporating changes into a checked-out revision.

-A

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.

-E, -e

These options specify conflict styles that generate less information than -A. See diff3(1) for details. The default is -E. With -e, rcsmerge does not warn about conflicts.

-ksubst

Use subst style keyword substitution. See co(1) for details. For example, -kk -r1.1 -r1.2 ignores differences in keyword values when merging the changes from 1.1 to 1.2. It normally does not make sense to merge binary files as if they were text, so rcsmerge refuses to merge files if -kb expansion is used.

-p[rev]

Send the result to standard output instead of overwriting the working file.

-q[rev]

Run quietly; do not print diagnostics.

-r[rev]

Merge with respect to revision rev. Here an empty rev stands for the latest revision on the default branch, normally the head.

-T

This option has no effect; it is present for compatibility with other RCS commands.

-V

Print RCS's version number.

-Vn

Emulate RCS version n. See co(1) for details.

-xsuffixes

Use suffixes to characterize RCS files. See ci(1) for details.

-zzone

Use zone as the time zone for keyword substitution. See co(1) for details.

rcsmerge -p -r2.8 -r3.4 f.c >f.merged.c

Then examine f.merged.c. Alternatively, if you want to save the updates to 2.8 in the RCS file, check them in as revision 2.8.1.1 and execute co -j:

ci -r2.8.1.1 f.c co -r3.4 -j2.8:2.8.1.1 f.c

As another example, the following command undoes the changes between revision 2.4 and 2.8 in your currently checked out revision in f.c.

rcsmerge -r2.8 -r2.4 f.c

Note the order of the arguments, and that f.c will be overwritten.

RCSINIT

options prepended to the argument list, separated by spaces. See ci(1) for details.