From: utzoo!decvax!ucbvax!C70:info-cpm Newsgroups: fa.info-cpm Title: unix-like directory tree stuff for CP/M Article-I.D.: ucb.1288 Posted: Sat Jun 5 00:28:11 1982 Received: Sat Jun 5 05:23:53 1982 >From lauren@Ucla-Security Sat Jun 5 00:27:51 1982 Good luck. Be sure to keep in mind that once you leave the linear directory structure, you are vulnerable to a whole new class of problems... that's why Unix (and MARC) use a completely different filesystem structure from CP/M. Be sure to include utilities like icheck, dcheck, ncheck, and clri to fix the sorts of problems that will no doubt appear frequently, given the way CP/M manages its free space. You also might try reducing the minimum CP/M block allocations size -- MARC uses 256 bytes which results in considerably more useful space but (surprisingly) no measurable additional overhead in most applications. Interestingly, a technique such as you described was attempted and rejected in an early pre-MARC system... the problems started to outweigh the benefits pretty quickly. One problem that you will certainly face is that most CP/M programs are very strict about the sorts of filenames they will accept, so you end up stuck with the usual CP/M limitations, which aren't much fun. There are a variety of other pitfalls as well, all of which eventually led to the conclusion that it was better to stop trying to build mountains on a foundation of sand, scrap the CP/M filesystem completely, and implement a full Unix filesystem from scratch -- which is how MARC ended up. --Lauren--