[libvirt] libvirt API to write sectors on a device

Hello,***I am able to compile libvirt samples on my KVM hypervisor. (I edited and recompiled info.c code) *I am creating a sample code to read/write disk devices. With method *virDomainBlockPeek I can** read sectors from a given device attached to a KVM virtual guest.**I am not able to* find an API to write sectors on a disk: am I missing something ?Is there such method to write sectors from a given virtual disk ? Thanks,Francesco