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From:	James Hu <jxh AT despammed DOT com>
Subject:	Re: About ENV?
Date:	Fri, 18 Oct 2002 15:56:34 +0000 (UTC)
Organization:	Despammed
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In article <3DAFAAB7 DOT 6070502 AT 21cn DOT com>, Huang. wrote:
> Why env in cygwin work like these:

I am sure this is off topic, since all UNIX shells based on Bourne
shell will behave this way.  This is not specific to Cygwin.

> $ AAAA=aaa echo $AAAA

This syntax says: Set variable AAA to aaa in the environment of the
command "echo $AAA".  However, the command "echo $AAA" will echo the
value of variable AAA in the current environment, since the expansion
of variables occurs before the command is executed.

> $ AAAA=aaa; echo $AAAA
> aaa

According to the explanation above, this is expected behavior.

> $ echo $AAAA
> aaa

According to the explanation above, this is expected behavior.

To do what I think you want to test try the following:

     AAA=bbb eval 'echo $AAA in' ; echo $AAA out
or   AAA=bbb sh -c 'echo $AAA in' ; echo $AAA out
or   (AAA=bbb; echo $AAA in) ; echo $AAA out

All of these commands involve echoing the value of AAA in an environment
that is in the inner scope of the environment of the command line.

-- James



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