Re: [PATCH 5.005_63 IO] Avoid shelling on backwhacks

[simon@brecon.co.uk (Simon Cozens)]

Ilya Zakharevich (lists.p5p):
>> I'm not sure about this one. I'm really not sure about this one.
>> Somebody will find a clever way of breaking it, no doubt, but it
>
>Or not escape it.  Depending on a phase of the moon on DOSISH systems,
>where SH-ish shells may decide to live \a to mean \\a to facilitate
>usage of DOSISH paths (surprizingly, the only thing I know which is
>broken by this option in OS/2 pdksh is one subtest in the Perl test
>suite ;-).

Bother. I knew someone would. :)

>What is your motivation?  Why you consider unbackwacking an important
>case to optimize?

It's *a* case to optimize, and I believe in not shelling out if
at all avoidable. There's also the fact that backwhacking things that
look like shell metacharacters turns them into things that aren't, and
so backwhacking should be a fundamental thing to consider if you're
doing this.

Uh. I didn't explain that very well.

If you optimise, say, asterisks, you might want to expand \*
If you deal with the backslash, you'll find you didn't need to deal with
the asterisk at all.

-- 
About the use of language: it is impossible to sharpen a pencil with a blunt
ax.  It is equally vain to try to do it with ten blunt axes instead.
		-- Edsger Dijkstra

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