xemu/docs/qmp
Stefan Hajnoczi 8593898109 Use qemu-project.org domain name
qemu.org is held by a third-party and no core community contributor has
access to the DNS configuration.  This leaves the website exposed to
outages due to DNS issues or IP address changes.  For example, if the
web server IP address needs to change we cannot guarantee qemu.org will
point to it!

The newer qemu-project.org domain name is owned by Anthony Liguori
<anthony@codemonkey.ws>.  You can confirm this by querying the whois
information.  Also note that the #qemu IRC channel topic already
references qemu-project.org.

Short of having a dedicated legal entity to hold the domain name on
behalf of the community, qemu-project.org seems like the safest bet.

Let's replace references to qemu.org with qemu-project.org.

Note that git-submodule(1) does not detect URL changes.  The following
commands clear out and re-initialize all submodules to ensure you are
using the latest URLs:

  $ git submodule deinit . # you'll be warned if you have local changes
  $ rm -rf .git/modules    # also clear cached .git/ directories
  $ git submodule update --init

Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1381495958-8306-1-git-send-email-stefanha@redhat.com
Signed-off-by: Anthony Liguori <aliguori@amazon.com>
2013-10-11 09:34:56 -07:00
..
qmp-events.txt QMP: qmp-events.txt: alphabetical order fix and other minor changes 2013-09-18 08:57:02 -04:00
qmp-spec.txt QMP: Update qmp-spec.txt 2013-09-18 08:57:02 -04:00
README Use qemu-project.org domain name 2013-10-11 09:34:56 -07:00

                          QEMU Machine Protocol
                          =====================

Introduction
------------

The QEMU Machine Protocol (QMP) allows applications to operate a
QEMU instance.

QMP is JSON[1] based and features the following:

- Lightweight, text-based, easy to parse data format
- Asynchronous messages support (ie. events)
- Capabilities Negotiation

For detailed information on QMP's usage, please, refer to the following files:

o qmp-spec.txt      QEMU Machine Protocol current specification
o qmp-commands.txt  QMP supported commands (auto-generated at build-time)
o qmp-events.txt    List of available asynchronous events

[1] http://www.json.org

Usage
-----

You can use the -qmp option to enable QMP. For example, the following
makes QMP available on localhost port 4444:

$ qemu [...] -qmp tcp:localhost:4444,server,nowait

However, for more flexibility and to make use of more options, the -mon
command-line option should be used. For instance, the following example
creates one HMP instance (human monitor) on stdio and one QMP instance
on localhost port 4444:

$ qemu [...] -chardev stdio,id=mon0 -mon chardev=mon0,mode=readline \
             -chardev socket,id=mon1,host=localhost,port=4444,server,nowait \
             -mon chardev=mon1,mode=control,pretty=on

Please, refer to QEMU's manpage for more information.

Simple Testing
--------------

To manually test QMP one can connect with telnet and issue commands by hand:

$ telnet localhost 4444
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
{
    "QMP": {
        "version": {
            "qemu": {
                "micro": 50, 
                "minor": 6, 
                "major": 1
            }, 
            "package": ""
        }, 
        "capabilities": [
        ]
    }
}

{ "execute": "qmp_capabilities" }
{
    "return": {
    }
}

{ "execute": "query-status" }
{
    "return": {
        "status": "prelaunch", 
        "singlestep": false, 
        "running": false
    }
}

Please, refer to the qapi-schema.json file for a complete command reference.

QMP wiki page
-------------

http://wiki.qemu-project.org/QMP