KLENSIN@INFOODS.MIT.EDU (John C Klensin) (02/12/88)
We set up some command procedures of our own after a round of discussion about getting current directories and other things into the prompt, and some postings on the list a year or so back. We found them a little unsatisfactory for reasons that have already been mentioned in other messages and submitted an SPR. The SPR said, in essence, that it should be possible to specify any sensible lexical function for dynamic execution (one execution per time the prompt goes up). It also pointed out that, while permitting a lexical function would be very general and probably as easy to do, that facility for putting dynamic information into prompts existed even in [shudder] MS-DOS. I note that the ability to say F$FAO(... F$ENVIRONMENT(...)...) with appropriate uses of F$EXTRACT can produce the output of any of the "use the following instead of SET DEFAULT so it can call SET PROMPT at appropriate times" strategies that have been posted. The strategy is, of course, not unprecedented: Multics has had a facility for specifying a user procedure to be called instead of the default thing that displays prompts for ten or fifteen years and procedures that do the majority of the most-asked-for things only slightly less long. The response to the SPR was of the "good idea, wonder why no one ever suggested that before, we will forward it to engineering and maybe they will do something about it" variety. [Disclaimer: that is a report of an impression, not either a quote or a Digital policy statement]. It does suggest that a small lobbying effort would be in order from anyone who thinks this sort of facility is important. I hope this goes without saying, but such lobbying should be directed, not at me or at the list, but at Digital through whatever channels you have available.