GNU RCS

Free plan

What GNU RCS is

GNU RCS is free, open-source revision-control software for managing changing files. It automates storing, retrieving, logging, identifying, and merging successive revisions. The project lists source code, programs, documentation, graphics, papers, and form letters as suitable material. RCS keeps a complete copy of the newest version and records earlier versions as reverse differences, called deltas. GNU Diffutils compares versions to find changes. A normal installation includes ci, co, ident, merge, rcs, rcsclean, rcsdiff, rcsmerge, and rlog commands for checking files in and out, inspecting revisions, cleaning files, comparing versions, and merging work. Binary files are supported with reduced functionality. Its centralized model keeps versions on one filesystem or machine and allows editing by one person at a time. RCS is self-hosted and supports file locking. Version 5.10.1 is listed as released on 2022-02-02. The software is licensed under GPL version 3 or any later version, with online HTML, ASCII, and PDF manuals.

Who it suits

GNU RCS suits individuals managing frequently revised files on a single filesystem or machine. It is aimed at source code, documents, graphics, papers, and similar material where one person edits at a time.

What it does well

Free software under GPL version 3 or later
Automates storing, retrieving, logging, and merging revisions
Supports binary files with reduced functionality
Includes commands for comparison and revision management
Self-hosted with file locking

What to know first

Centralized storage uses one filesystem or machine
Editing is limited to one person at a time
Binary-file functionality is reduced
Latest listed release is from 2022

Plans

Plan	Billed and limits	Price
GNU RCS	Free software under GPL version 3 or later · Stores versions on a single filesystem or machine	Free

As gnu.org lists them, read 11 Oct 2026. The maker's own page has the final word.

Verdict

GNU RCS provides centralized, self-hosted revision management with a broad command-line toolkit. Its single-machine and one-editor model is a key constraint for collaborative workflows.

Facts from GNU RCS's own pages

Binary files: RCS can handle binary files, although functionality is reduced for them. · gnu.org, 11 Oct 2026
Commands: A normal installation includes ci, co, ident, merge, rcs, rcsclean, rcsdiff, rcsmerge, and rlog. · gnu.org, 11 Oct 2026
Comparison engine: RCS uses GNU Diffutils to find differences between versions. · gnu.org, 11 Oct 2026
Concurrency limit: RCS works with versions stored on a single filesystem or machine and edited by one person at a time. · gnu.org, 11 Oct 2026
Development: The project describes GNU RCS development as a volunteer effort and points to Savannah for development sources and issue trackers. · gnu.org, 11 Oct 2026
Documentation: The GNU RCS manual is available online in multiple formats, including HTML, ASCII text, and PDF. · gnu.org, 11 Oct 2026
History storage: RCS stores a full copy of the most recent version and reverse differences called deltas for earlier versions. · gnu.org, 11 Oct 2026
License: GNU RCS is free software under the GNU General Public License, version 3 or, at the user's option, any later version. · gnu.org, 11 Oct 2026
Purpose: GNU RCS manages multiple revisions of files and automates storing, retrieving, logging, identifying, and merging revisions. · gnu.org, 11 Oct 2026
Release: The project page lists version 5.10.1, released on 2022-02-02, as its latest release. · gnu.org, 11 Oct 2026
Security reports: The project says security reports that should not be made public immediately can be sent directly to the maintainer. · gnu.org, 11 Oct 2026
Support: The project lists bug-rcs for bug reports and help-rcs for feature requests and user support. · gnu.org, 11 Oct 2026
Use cases: The project describes RCS as useful for frequently revised text such as source code, programs, documentation, graphics, papers, and form letters. · gnu.org, 11 Oct 2026

Where GNU RCS stands on Freedom251

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