Re: [kvm-unit-tests PATCH v3 3/6] arch-run: reduce return code ambiguity

[Paolo Bonzini <pbonzini@redhat.com>]

On 02/03/2016 13:57, Radim Krčmář wrote:
> 2016-03-01 22:29+0100, Paolo Bonzini:
>> On 29/02/2016 19:53, Andrew Jones wrote:
>>> +	errors=$("${@}" 2>&1 1>&${stdout} | tee >(cat - 1>&2); exit ${PIPESTATUS[0]})
>>
>> Whoa! :)  So stdout goes to {stdout} and from there to the real stdout;
>> stderr instead is tee'd to stderr and $errors.
> 
> Yeah. :)
> 
>> Is the "tee" and "cat" necessary?  Can you just use printf somewhat like:
> 
> They are, if you want want to improve chances of getting the original
> order of stdout and stderr.

Getting the original order can't really work if you use separate file
descriptions.

I'm not sure how you would have something on stderr, except on the very
last line?  The idea being that 1) the test only writes to stdout 2)
QEMU only writes to stderr 3) QEMU exits after writing to stderr.  If
this is true, the proposed assignment/printf pair works just fine.

>>> +	temp_file RUNTIME_arch_run <(echo "#!/bin/bash"; cat scripts/arch-run.bash "$TEST_DIR/run")
>>
>> Please use a pipe instead of a <(...):
> 
> (Is it for aesthetic reasons?)

Yes, nothing more.  Also, gzip has "-c", might as well use it.

Paolo