[Libguestfs] guestunmount issues

Hello everyone! I'm playing with guestunmount and got the following issues: 1) guestunmount never returns 3 (not mounted) - i guess it's a bug at guestunmount.c:223 2) I don't know whether it's a bug in guestunmount or fusermount, but on my machine while executing on second "guestunmount" I get "guestunmount: failed to unmount {...}: fusermount: failed to unmount {...}: Invalid argument" while, according to guestunmount.c, guestunmount should return something like "entry for {} not found" 3) gives me "Invalid argument" as well, while handles this error successfully and returns "not mounted". (strace logs attached) I have a custom centos7-based distro, but I don't think it matters. I'd like someone to compare results with mine, and, possibly, give me some explanations about why it's going like this and how to distinguish non-mounted mountpoints from busy ones (I guess I'll have to parse umount {} output). Thanks in advance! -- Your sincerely, Maxim Perevedentsev