[libvirt-users] error : virPidFileAcquirePath:345 : Failed to acquire pid file '/home/corey/.libvirt/libvirtd.pid': Resource temporarily unavailable

Hi all, When I try to start libvirtd, using "libvirtd -d", error notification shown below:error : virPidFileAcquirePath:345 : Failed to acquire pid file '/$HOME/.libvirt/libvirtd.pid': Resource temporarily unavailable Using "libvirtd -v", show: "libvirtd: error: Unable to obtain pidfile. Check /var/log/messages or run without --daemon for more info." The file "libvirtd.pid" only contains "2010" without any other infomation. I have checked that libvirtd has been installed in "/libvirt/sbin" with binary format by self-compiled. So how can I solve the problem? Or how to start libvirtd? Meanwhile, virsh can't search "libvirt-sock", because the libvirtd is not started successfully. Thanks a lot! Corey