[Libvir] RFC 'xen like scripts'

Currently in Xen it is very easy to prototype a certain function related to binding host hardware to virtual hardware. The script gets an argument, can do anything it wants and returns another argument, or better: writes it to the xen-store. I was reviewing the current iSCSI code, because I cannot switch to libvirt with the current implementation. (From OpenSolaris, I migrated to NetApp.) So I pose a simple request: would anyone be able to create a xen-like storage backend that in principle passes the URI to a script (that runs as a fork) this script sets for example an envirionment variable or text output, the code uses this envirionment variable as path to the storage area. And a great prototypable system has been created. It could be a question by some: 'why doesn't he write a simple implementation in C?' basically: I'll will do this, no worries about that one, but I would like to be able to prototype my programs first. Is there anyone who wants to spend a few hours on this simple request, or could someone tell me what he/she doesn't like about setting the environment? Other solutions are ofcourse possible. Waiting for your comments, Stefan de Konink