On 10 February 2012 18:25, Chris Siebenmann <cks_AT_cs.toronto.edu> wrote:
> | > €I'm coming in late to an ongoing discussion: it sounds like there's
> | > something wrong with Byron's version of rc apart from being written from
> | > scratch for Unix (and not quite implementing Plan 9 rc syntax, since it
> | > doesn't have 'if not'). Do you have a pointer to where I could read more
> | > about this?
> |
> | I'm not aware of a an in-depth analysis of all differences, but the
> | main ones are:
> |
> | - Byron introduced the export keyword
> | - Byron broke the default syntax with the else keyword (vs if not)
> | - Byron does not export functions into the environment
> | - Byron does not export variables into the environment
> | - No rcmain counterpart in Byrons version
> |
> | I'm sure I have missed some other aspects.
>
> Hmm, something is odd here. I am a long-term user of the Byron version
> of rc (I started using it when it was the only choice for an rc-like
> thing on Unix), and the main version I have used and always seen does
> not have an export keyword and automatically exports functions and
> variables into the environment[*]. It does have the two defects of else
> vs 'if not' and not having an rcmain.
>
> (I just grabbed the rc-1.7.1 source from http://rc-shell.slackmatic.org/
> and verified this in the manpage.)
>
> If there is some mutant version of Byron's rc with these three things,
> it is, well, surprisingly mutant. I'd go so far as to call it mutilated.
Ok, I might have consumed my Byron rc hacks that resulted in an
obscure rci version (about 10 years ago) with Byrons version. I
apologize for remembering this wrong and take back the two
accusations.
> [Another difference between Byron rc and Plan 9 rc is that Byron rc
> can run a function every time before the prompt is printed; I don't
> think this is part of Plan 9 rc, or at least I can't find it in the
> manpage.]
Ok, good point.
Thanks,
Anselm
Received on Sat Feb 11 2012 - 11:06:49 CET