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From: Xu Qiang <Qiang.Xu@fujixerox.com>
To: Giorgos Keramidas <keramida@ceid.upatras.gr>,
	Xu Qiang <Qiang.Xu@fujixerox.com>
Date: Fri, 12 Aug 2005 10:38:20 +0800
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Cc: dpk <dpk@dpk.net>, freebsd-questions@freebsd.org
Subject: RE: Help on bash script?
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Giorgos Keramidas wrote:
> On 2005-08-12 10:16, Xu Qiang <Qiang.Xu@fujixerox.com> wrote:
>> Btw, can we "export" a value in the sub-shell back to the parent?
> =

> Only through `backquote subtitution', as the child process cannot
> affect the environment of the parent process.
> =

> 	value=3D`shell command`
> 	value=3D$(shell command)

Ah, yes, I mistakened it. The "export" mechanism is to preserve the value f=
rom the parent to the child, not the other direction, as described in the b=
ook "The Unix Programming Environment" by Brian Kernighan and Rob Pike. =


Thanks,
Xu Qiang