Re: expand: Do not quote backslashes in unquoted parameter expansion

[Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>]

On Tue, Mar 27, 2018 at 11:16:29AM +0200, Harald van Dijk wrote:
>
> If you say that quote removal takes place on the original token (meaning
> before parameter expansion), and if parameter expansion takes place before
> pathname expansion, then there's nothing left to allow \* to behave
> differently from *.

Either you misunderstood me or you misread POSIX.  Quote removal
never applies to the backslashes which occur as a result of parameter
expansion:

	2.6.7 Quote Removal
	The quote characters ( <backslash>, single-quote, and
	double-quote) that were present in the original word shall be
	removed unless they have themselves been quoted.

It's clear that only quote characters in the *original* word will
be removed.

> POSIX never actually says this optimisation is allowed. The only thing that
> allows it is the fact that it produces the same results anyway. If that
> stops, then checking the file system for matches becomes required.

It doesn't disallow it either.  Can you show me a shell that doesn't
apply this optimisation?

Cheers,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
--
To unsubscribe from this list: send the line "unsubscribe dash" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html