Subject: Re: ash & POSIX 1003.2 q's
To: Garrett Wollman <>
From: Paul DuBois <>
List: tech-userlevel
Date: 01/27/1997 11:23:37
Garrett Wollman writes:
> > I'm a little disappointed that pdksh doesn't use something
> > like yacc, but perhaps there is a good reason (the tables get too big?
> > suboptimal generated parsers?)
> Tom Duff once noted that the grammar given in the AT&T sh(1) man page
> did not allow even such simple commands as `who | wc'.  He then went
> on to say, ``[There is] an even darker secret: nobody really knows
> what the Bourne shell's grammar is.''  (Sorry, I can't find the
> reference for this right now.

It's on the last page of Duff's paper on the rc shell (Rc - A Shell
for Plan 9 and UNIX Systems).

Paul DuBois
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