Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!seismo!husc6!rutgers!labrea!decwrl!pyramid!uccba!hal!ncoast!allbery From: allbery@ncoast.UUCP (Brandon Allbery) Newsgroups: comp.unix.wizards Subject: Re: Symbolic Links Message-ID: <4494@ncoast.UUCP> Date: Wed, 9-Sep-87 19:52:28 EDT Article-I.D.: ncoast.4494 Posted: Wed Sep 9 19:52:28 1987 Date-Received: Sat, 12-Sep-87 06:32:52 EDT References: <8731@brl-adm.ARPA> <2789@ulysses.homer.nj.att.com> Reply-To: allbery@ncoast.UUCP (Brandon Allbery) Followup-To: comp.unix.wizards Organization: Cleveland Public Access UN*X, Cleveland, Oh Lines: 48 As quoted from <1119@bsu-cs.UUCP> by dhesi@bsu-cs.UUCP (Rahul Dhesi): +--------------- | There is no reason why the value of SYS could not be relative. | | $ setlink ABC /usr/include/sys | $ setlink EFG ../jkl | $ setlink XYZ alpha | $ cd $ABC/$EFG/$XYZ | $ pwd | /usr/include/jkl/alpha | $ | | ABC, EFG, and XYZ look like environment variables, but they are known | to the kernel and accessed via a hash table, not a sequential search. | The hash table itself is accessible via a special entry in the normal | environment so that, for example, a library function can look for the | environment variable LINKTABLE and get some value that will let it | access the hash table directly, so the kenrel need not be involved in | all accesses, only those that are needed in system calls. +--------------- Anyone for TOPS-10/TOPS/20/VMS "DEFINE"? Logical names have been around for a long time; that they aren't in UNIX may indicate that they aren't the panacea you think. (Anyone know for sure? DMR?) +--------------- | Pick one: | | [ ] symbolic links available around 1983, that largely work | and are useful, though they lead to some confusing | situations because the kernel and the user may interpret | ".." differently; may be up to 255 characters long | | [ ] symbolic links designed carefully to lead to no confusion; | approved after much consideration by four layers of | bureacracy; not currently available, and probably won't be | until 1989; will probably be limited to 14 characters +--------------- Having had to (attempt to) repair disasters caused by the first, I'll opt for the second. Nobody said they had to _stay_ limited to 14 characters. -- Brandon S. Allbery, moderator of comp.sources.misc {{harvard,mit-eddie}!necntc,well!hoptoad,sun!mandrill!hal}!ncoast!allbery ARPA: necntc!ncoast!allbery@harvard.harvard.edu Fido: 157/502 MCI: BALLBERY <> All opinions in this message are random characters produced when my cat jumped (-: up onto the keyboard of my PC. :-)