[libvirt-users] How to specify the libvirtd in connect call

Hi, Here is my situation, I install libvirt in a non-default directory and start libvird with sudo. While I can connect virsh to libvirtd using "virsh --connect qemu:///system", I fail to connect my app using "virConnectOpen("qemu:///system")", which complains "unable to locate libvirtd daemon in $PATH". Then, I take another try and add the path of libvirtd in env variable PATH. Unfortunately, it doesn't work. I read through the api reference and find no place to specify this path explicitly. Thanks for any tip. Harvey