Re: [PATCH blktests 1/4] tests/nvme/rc: Modify the approach for disabling and re-enabling Ctrl-C

[Bart Van Assche <bvanassche@acm.org>]

On 8/8/19 1:08 PM, Logan Gunthorpe wrote:
> On 2019-08-08 2:05 p.m., Bart Van Assche wrote:
>> Avoid that the following error messages are reported when redirecting stdin:
>>
>> stty: 'standard input': Inappropriate ioctl for device
>> stty: 'standard input': Inappropriate ioctl for device
>>
>> Cc: Logan Gunthorpe <logang@deltatee.com>
>> Cc: Johannes Thumshirn <jthumshirn@suse.de>
>> Fixes: a987b10bc179 ("nvme: Ensure all ports and subsystems are removed on cleanup")
>> Signed-off-by: Bart Van Assche <bvanassche@acm.org>
>> ---
>>   tests/nvme/rc | 4 ++--
>>   1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/tests/nvme/rc b/tests/nvme/rc
>> index d4e18e635dea..40f0413d32d2 100644
>> --- a/tests/nvme/rc
>> +++ b/tests/nvme/rc
>> @@ -36,7 +36,7 @@ _cleanup_nvmet() {
>>   	fi
>>   
>>   	# Don't let successive Ctrl-Cs interrupt the cleanup processes
>> -	stty -isig
>> +	trap '' SIGINT
> 
> Did you test this? Pretty sure I tried using trap and it didn't work,
> probably because it's already running inside a trapped SIGINT.
> 
> Maybe it'd be better to just ignore any errors stty produces and pipe to
> /dev/null?

Hi Logan,

I don't think that redirecting the stty errors would be sufficient 
because Ctrl-C still works even if stdin, stdout and stderr are 
redirected. A command like sleep 60 </dev/null >&/dev/null can be 
interrupted with Ctrl-C but stty -isig >&/dev/null does not suppress 
Ctrl-C if stdin is redirected.

Are there other trap SIGINT statements in the blktests code? Does that 
mean that I overlooked something?

Thanks,

Bart.