On 07/23/2017 08:49 PM, 陳培泓 wrote:
> I check to the newest version of qemu.

You're still top-posting, which makes it really hard to answer your
questions.

> 
> and do the cmds to install followed by the documents in github:
> 
>> mkdir build
>> cd build
>> ../configure
>> make
> 
> 
> and it show nothing errors​
> It's the version when I enter qemu-img --help:
> 
> and I execute encrypt format(luks) to the qcow2 file:
> 
> ​

Attaching inline images is a horrible waste of bandwidth, compared to
copying-and-pasting the terminal text directly.  Furthermore, your email
is illegible in a plain-text client (like what I prefer to use), and
requires that I switch to html view to even understand what you are asking.

> always shows the error, how to solve it?​

Transcribing one of your images:

> pahome@pahome-QW09:~/git/qemu/build$ ./qemu-img --help
> qemu-img version 2.9.0 (v2.9.0-dirty)

You aren't building the latest version of qemu.git.  If you were, you'd
be getting something like this:

$ ./qemu-img --help | head -n1
qemu-img version 2.9.50 (v2.9.0-2519-gb52f59694d)

Before you can complain that something recently added isn't working, you
first have to make sure you are building the right version.

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org