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Re: mksh import



On Wed, Jan 05, 2011 at 05:42:46AM +0000, David Holland wrote:
> On Tue, Jan 04, 2011 at 10:57:05PM -0500, Thor Lancelot Simon wrote:
>  > Our existing /bin/sh has the full set of POSIX shell features and thus
>  > what you can't do with it, you can't do in a portable shell script anyhow.
> 
> That's not quite true any more. Someone got a bunch of random kshisms
> put into POSIX, and at least some of them unimplemented and unwanted
> misfeatures, like cd -L.

Try "cd foo/.." when foo is a symlink that is found through $CDPATH.
The ksh 'logical cd' just doesn't DTRT at all.

Together with 'fc' (I've no idea why the 'command history' utility
is f*c*), and one option to 'command' which doesn't execute stuff at all.

Then there is the crap about only using 'builtin' versions of standard
utilities after doing the $PATH search and finding the program in the
default place. That would just slow everything down massively.

About the only other place we don't follow posix is in dyamically
expanding $PS1, here again the posix rules are a description of
a specific implementation, not something that is likely to be
implementable inside a different framework.

        David

-- 
David Laight: david%l8s.co.uk@localhost


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