An earlier version of this paper was published in Software--Practice & Experience 15, 7 (July 1985), 637-654.
** Pairs of RCS and working files can actually be specified in 3 ways: a) both are given, b) only the working file is given, c) only the RCS file is given. If a pair is given, both files may have arbitrary path prefixes; RCS commands pair them up intelligently.
*** Note that this problem is entirely different from the atomicity problem. Atomicity means that concurrent update operations on the same RCS file cannot be permitted, because that may result in inconsistent data. Atomic updates are essential (and implemented in RCS), but do not solve the conflict discussed here.
* This auto-checkout extension is available only in some versions of MAKE, e.g. GNU MAKE.
* The rcsclean and rcsfreeze commands are optional and are not always installed.