Hi, sorry for the late reply, this email fall behind in my queue. On Friday, 15 March 2019 19:00:18 CEST Chintan Patel wrote: This was reported years ago: https://bugzilla.redhat.com/show_bug.cgi?id=1092583 While adding a querystring optional argument looks like an easy solution, in reality it opens a can of worms, as it would be a generic passthrough for options, and not really easy to handle by libguestfs. For few more details, see also the following email with a possible way to implement this that I wrote some time ago: https://www.redhat.com/archives/libguestfs/2015-December/msg00016.html One additional argument not written in the email is that using a query string as-is works only when using the "direct" backend (i.e. libguestfs runs qemu directly); since we support also launching qemu using libvirt (the "libvirt" backend), this cannot work in that case. This is why IMHO a proper fix is to a) split the query string in its key/value components b) pass these key/value's via the add_drive API c) use the various parameters properly depending on the protocol of the disk, and on the libguestfs backend - the commit message is very terse, and in case it would need a bit more explanation - the new optional parameter is not documented in the documentation text of the add_drive API - 'fullPath' in lib/drives.c is leaked - the new 'query' struct member in common/options/options.h is leaked - use safe_asprintf instead of asprintf in lib/drives.c, so it will abort already in case of failure - why was xmlURIUnescapeString() used? - in case of nbd URIs with a socket, now the path to the socket will be both in the server name, and as query string; see the various tests in fish/test-add-uri.sh Thanks, -- Pino Toscano