On Wed, Feb 04, 2004 at 10:44:24PM +1000, Andrew Pollock wrote:
|| On Wed, Feb 04, 2004 at 05:28:27PM +1100, Lex Hider wrote:
|| > while [ x"$1" != x ]; do
|| > ...
|| > done
|| >
|| > the same as using the -z flag for test.
... not considering the negation in there.
I would write [ "${1:+x}" ], or rather even [ "${1+x}" ], distinguishing
empty and undefined.
|| > It just looks like a weird way of doing things that occur frequently.
|| Don't take this as gospel, but I've seen it around a lot too, particularly
|| in older-school shell scripts. I'm guessing it was done before the -z test
|| existed or something...
Or more likely, many people know = and !=, and know enough to implement
the test they need.
--
Vincent Zweije <zweije@xs4all.nl> | "If you're flamed in a group you
<http://www.xs4all.nl/~zweije/> | don't read, does anybody get burnt?"
[Xhost should be taken out and shot] | -- Paul Tomblin on a.s.r.
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