Path: utzoo!mnetor!uunet!husc6!bloom-beacon!gatech!mcnc!decvax!decwrl!labrea!rocky!andy From: andy@rocky.STANFORD.EDU (Andy Freeman) Newsgroups: comp.os.misc Subject: Re: What should completion look like on Unix? Message-ID: <926@rocky.STANFORD.EDU> Date: 4 Jan 88 21:06:45 GMT References: <1971@cup.portal.com> <1169@nmtsun.nmt.edu> <588@kuling.UUCP> <871@rocky.STANFORD.EDU> <476@athos.rutgers.edu> <882@rocky.STANFORD.EDU> <2028@chinet.UUCP> Reply-To: andy@rocky.UUCP (Andy Freeman) Organization: Stanford University Computer Science Department Lines: 53 In article <2028@chinet.UUCP> ignatz@chinet.UUCP (Dave Ihnat) writes: >In article <882@rocky.STANFORD.EDU> andy@rocky.STANFORD.EDU (Andy Freeman) >writes: [I was responding to Charles Hedrick's comment that when invoking a program, instead of a command (builtin to csh/sh fans), the default TOPS-20 exec doesn't offer any help.] >> In other words, TOPS-20 at its worst is like unix.... Dave Ihnat objects to this comment as being sheer opinion and thinks it should have been labeled as humorous. I was being overly snide, my apologies, but the comment is factual. Ignoring tcsh (and 4.3bsd csh with filec set), the command parsers in unix shells DON'T have any help facilities for either commands or programs; they only have line editing commands. That's all that the TOPS-20 exec (shell to unix fans) does for invoked program arguments. (Remember, the exec knows more about commands, so the command line parser has recognition/ help for arguments whether they are file names or other kinds of arguments.) tcsh (and 4.3bsd csh with filec set) recognizes command and program names (as does TOPS-20) and has recognition for file names as arguments. It does this no matter what type of arguments the command/program is expecting; most unix arguments are file names so this isn't wrong too often. Adding tcsh capability to the TOPS-20 exec (shell to unix fans) would take about 30 minutes but it hasn't been a big priority here. (We just figured it out so that I could quote the time to implement.) Why? Well, it only affects how the exec parses command line arguments for programs and since the exec doesn't know what their arguments look like (they may not be file names), it would recognize a file name even though the program wants something else. Tcsh does this and it isn't fatal (just don't type ), but other TOPS-20 recognition is always type-correct and this would be an anomaly. The second factor is that TOPS-20 programs parse their own arguments because they can do correct recognition (they know what they want); command line arguments are merely shorthand and some programs don't even bother to accept them. >> Is this another unix tty driver "feature"? (I knew it dropped >> characters, is it also this inflexible?) ... Hedrick had just said that adding a help character would be inefficient under unix' tty driver. That sounds inflexible to me. I've been "trained" to avoid the things that convinces the 4.nBSD terminal drivers to drop characters. Other unix' may be better. TOPS-20 is dead and unix isn't, but that doesn't mean that unix does everything better. I've used both for several years and they have different strengths. -andy -- Andy Freeman UUCP: {arpa gateways, decwrl, sun, hplabs, rutgers}!sushi.stanford.edu!andy ARPA: andy@sushi.stanford.edu (415) 329-1718/723-3088 home/cubicle