ca9567e234
With capability negotiation support clients will only have a chance to check QEMU's version (ie. issue 'query-version') after the negotiation procedure is done. It might be useful to clients to check QEMU's version before negotiating features, though. To allow that, this commit adds the QEMU's version object to the greeting message. Not really sure this is needed, but doesn't hurt anyway. Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
66 lines
1.7 KiB
Plaintext
66 lines
1.7 KiB
Plaintext
QEMU Monitor Protocol
|
|
=====================
|
|
|
|
Introduction
|
|
-------------
|
|
|
|
The QEMU Monitor Protocol (QMP) allows applications to communicate with
|
|
QEMU's Monitor.
|
|
|
|
QMP is JSON[1] based and has the following features:
|
|
|
|
- Lightweight, text-based, easy to parse data format
|
|
- Asynchronous events support
|
|
- Stability
|
|
|
|
For more information, please, refer to the following files:
|
|
|
|
o qmp-spec.txt QEMU Monitor Protocol current specification
|
|
o qmp-events.txt List of available asynchronous events
|
|
|
|
There are also two simple Python scripts available:
|
|
|
|
o qmp-shell A shell
|
|
o vm-info Show some information about the Virtual Machine
|
|
|
|
[1] http://www.json.org
|
|
|
|
Usage
|
|
-----
|
|
|
|
To enable QMP, QEMU has to be started in "control mode". There are
|
|
two ways of doing this, the simplest one is using the the '-qmp'
|
|
command-line option.
|
|
|
|
For example:
|
|
|
|
$ qemu [...] -qmp tcp:localhost:4444,server
|
|
|
|
Will start QEMU in control mode, waiting for a client TCP connection
|
|
on localhost port 4444.
|
|
|
|
It is also possible to use the '-mon' command-line option to have
|
|
more complex combinations. Please, refer to the QEMU's manpage for
|
|
more information.
|
|
|
|
Simple Testing
|
|
--------------
|
|
|
|
To manually test QMP one can connect with telnet and issue commands:
|
|
|
|
$ telnet localhost 4444
|
|
Trying 127.0.0.1...
|
|
Connected to localhost.
|
|
Escape character is '^]'.
|
|
{"QMP": {"version": {"qemu": "0.12.50", "package": ""}, "capabilities": []}}
|
|
{ "execute": "qmp_capabilities" }
|
|
{"return": {}}
|
|
{ "execute": "query-version" }
|
|
{"return": {"qemu": "0.12.50", "package": ""}}
|
|
|
|
Contact
|
|
-------
|
|
|
|
http://www.linux-kvm.org/page/MonitorProtocol
|
|
Luiz Fernando N. Capitulino <lcapitulino@redhat.com>
|