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Re: 3 simple steps to make booting/shutdown faster...

Behdad Esfahbod wrote:
On Sun, 17 Feb 2008 08:15:20 -0800, Arjan van de Ven wrote

This should really be fixed in bash to short-circuit.
well......... not sure it can be done in the bash language.
(it may well guarantee that both get executed)

There's nothing to execute there.  All the expansions happen first, so
if you have things like [ -n "$something" -a "`id`" = 0 ], the `id` call
is made before passing control to "test".  The short-circuit would just
happen in the evaluation in test.  There's no user-visible difference

If thats the case shouldn't a statement like that always be nested so that `id` is not called if it is not necessary, possibly saving many disk accesses? It would seem that using the more complex constructs could be much slower if all the cases are evaluated before testing any of them.

Andrew Farris <lordmorgul gmail com> www.lordmorgul.net
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