git cvsexportcommit

One-way bridge for the holdouts.

🎯 What & why

git cvsexportcommit takes a single Git commit and replays it onto a CVS working copy so it can be cvs commit-ed. It exists for teams forced to keep CVS as the system of record.

🧠 Mental model

Think of it as a patch courier: it generates a diff for one Git commit, applies it inside a CVS checkout, and optionally runs cvs commit with the same log message.

🛠️ Synopsis

    git cvsexportcommit [-h] [-u] [-w cvsworkdir] [-W] [-p] [-v]
                        [-c] [-f] [-a] [-m msgprefix]
                        [parent-commit] commit-id

Requires a CVS working directory checked out somewhere on disk;
specify it with -w or use -W to reuse the current Git work tree.

🎚️ Switches & options

Flag	What it does
`-c`	After applying, run cvs commit automatically
`-p`	Apply the patch with git apply --3way for cleaner merges
`-v`	Verbose; show the diff and apply progress
`-u`	Run cvs update on the work dir before applying
`-w <dir>`	Path to the CVS working directory to apply the commit into
`-W`	Use the current Git work tree as the CVS work dir (advanced)
`-f`	⚠️ Force the commit even if the tree is dirty or differs

💡 Use cases

Letting developers work in Git daily but mirror commits into a CVS system of record
Pushing a single bug fix from a Git fork back upstream to a CVS-based project
Bridging during a slow migration off CVS without losing day-to-day productivity
Automating per-commit replay in a pipeline that runs cvs commit at the end

🧪 Examples

Preview a commit against a CVS work dir

git cvsexportcommit -v -w /srv/cvswork/myproj HEAD

Update CVS, apply with 3-way, then commit

git cvsexportcommit -u -p -c -w /srv/cvswork/myproj HEAD

Export a specific commit by SHA

git cvsexportcommit -v -c -w /srv/cvswork/myproj 9f1c2ab^ 9f1c2ab

Use the Git work tree itself as the CVS work dir

git cvsexportcommit -W -c HEAD

🎓 Recommendations

Always run with -u first so you are exporting against the freshest CVS state.
Use -p; without 3-way apply, even tiny CVS-side drift will reject the patch.
Wire -c only into pipelines you trust; interactive use is safer without it.

🪤 Common pitfalls

The CVS checkout must be clean; a dirty work dir will produce wrong diffs or refuse to apply.
Binary files often need explicit CVS -kb flags; cvsexportcommit will not fix that for you.
Merge commits cannot be exported as a single cvs commit; export the parents individually.

🔗 Related modules

📝 Quiz

Hit each option, then Check answers. Score is recorded; Next is always open.