Re: [Qemu-devel] [PATCH RFC] qemu-io: Prefer stderr for error messages

[Kevin Wolf]

Am 12.12.2018 um 23:04 hat Eric Blake geschrieben:
> When a qemu-io command fails, it's best if the failure message
> goes to stderr rather than stdout.
> 
> Reported-by: Richard W.M. Jones <address@hidden>
> Signed-off-by: Eric Blake <address@hidden>
> ---
> 
> RFC because at least iotest 60 (found by -qcow2 -g quick) breaks due
> to reordering of output lines, and I'd rather know if we like this
> idea before bothering to revisit all affected iotests (including
> discovering if other slower ones have similar problems).

So if we decide to actually do this, should this be error_report()
instead so that HMP 'qemu-io' gets the errors printed to the monitor
rather than stderr? Though I think in that case, we'd also want to
redirect the messages that still go stdout to the monitor as well.

But as I said in another reply, I'm not sure if mixing stdout and stderr
with their different buffering settings is even a good idea in a mostly
interactive program.

Kevin