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Re: Command substitution

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From Greg Wooledge <wooledg@eeg.ccf.org>
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Subject Re: Command substitution
Date Wed, 3 Jun 2020 07:19:22 -0400
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On Tue, Jun 02, 2020 at 09:44:45PM -0400, Dale R. Worley wrote:
> Naively, I expect that

>     FOO="$( command2 )"
>     command1 "$FOO"
> 
> has the same effect as
> 
>     command1 "$( command2 )"
> 
> Has anyone pushed the boundaries of this and can tell me whether there
> are gotchas?

The main case where people care about the difference is when set -e is
in effect.  Otherwise, no, most people do not care.  If they cared, they
would be checking the exit status of command2 themselves, rather than
simply letting the shell proceed.

(And set -e should never be in effect.  But people don't listen when we
tell them that, so that situation persists.)

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Re: Command substitution Greg Wooledge <wooledg@eeg.ccf.org> - 2020-06-03 07:19 -0400

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