Re: .ONESHELL enhancement?

[Paul Smith]

On Fri, 2009-09-25 at 13:38 -0400, David Boyce wrote:
> I don't think that works exactly as you describe.

Hrm, you're right.  I have this vivid memory of a make variable that
could be set to a list of shells that would be considered "POSIX
shells", precisely for systems like Solaris, or even systems that
use /bin/dash or /bin/ksh or whatever, to allow them to declare that a
given shell should try to use the fast path even if it wasn't exactly
"/bin/sh".

But it doesn't exist in the code that I can find, so either I dreamed it
or someone suggested it but it was never added.

> Actually they are, in the sense that the spec says you're only
> guaranteed POSIX behavior if you (a) include .POSIX and (b) don't
> include any nonstandard special targets. Thus the presence of
> .ONESHELL explicitly sets you free from POSIX requirements even if
> .POSIX is present too.

Sure, but all .<TARGETS> have that quality.  And, of course, since it's
our choice to define what happens we can define that it still obeys
POSIX requirements if .POSIX is set :-).