From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [question kvm-unit-tests] issue about exec
Date: Tue, 29 Mar 2016 15:43:21 +0200
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	Hangaohuai <hangaohuai@huawei.com>
To: Andrew Jones <drjones@redhat.com>, Zhu Yijun <zhuyijun@huawei.com>
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On 29/03/2016 14:03, Andrew Jones wrote:
>> > 	I am running kvm-unit-tests, the Bash(version is low) on my server doesn't support the command 'exec', so I changed some codes in kvm-unit-tests.
> Hmm, I didn't know there were bash versions w/out exec. Is your bash
> really bash?

It could be the "{fd}<foo" feature, which according to
http://tiswww.case.edu/php/chet/bash/NEWS was introduced in 4.1:

----
This is a terse description of the new features added to bash-4.1 since
the release of bash-4.0.

[...]

p.  If the optional left-hand-side of a redirection is of the form
{var}, the shell assigns the file descriptor used to $var or uses $var
as the file descriptor to move or close, depending on the redirection
operator.
----

Yijun, I think using "10" unconditionally would work (i.e. replace {fd}
and $fd with 10).

Paolo

>> > 
>> > diff --git a/scripts/functions.bash b/scripts/functions.bash
>> > index f13fe6f..241ae0e 100644
>> > --- a/scripts/functions.bash
>> > +++ b/scripts/functions.bash
>> > @@ -12,9 +12,10 @@ function for_each_unittest()
>> >         local check
>> >         local accel
>> > 
>> > -       exec {fd}<"$unittests"
>> > +       #exec {fd}<"$unittests"