Thanks for your reply
what i want to know is that why there are many devices in $domain.xml, actully , i choose nothing in virt-manager?
so, Do i need to look at qemuDomainDefineXMLFlags()?
hours ago, i thought it's qemuDomainCreateWithFlags.

--
Have a good day

> -----原始邮件-----
> 发件人: Michal Privoznik <mprivozn@redhat.com>
> 发送时间: 2018年4月26日 星期四
> 收件人: "李卓瑶" <lizhuoyao@hikdata.com>, libvirt-users <libvirt-users@redhat.com>
> 抄送: shengyizju@163.com
> 主题: Re: [libvirt-users] how xml generated
> 
> On 04/26/2018 04:29 AM, 李卓瑶 wrote:
> > hi :
> >  i create a domain by virt-manager tool, then there is a xxx.xml generated in /etc/libvirt/qemu/.
> > so, my question is how the xx.xml generated? What the code involves in libvirt ?
> 
> Long story short, virt-manager invokes virt-install which generates XML
> string. This string (not yet saved onto disk, still just in memory) is
> then passed to libvirt API virDomainDefineXML() which parses it, does
> some sanity checking and finally formats it back and save it under
> /etc/libvirt/qemu/$domain.xml.
> 
> Codewise, you want to be looking at qemuDomainDefineXMLFlags().
> 
> Michal