From b8fc61bd9b87f9d55d37cd52f584f7706b2af078 Mon Sep 17 00:00:00 2001 From: "Richard W.M. Jones" Date: Tue, 20 Mar 2012 09:11:16 +0000 Subject: todo: Document proposed attach-method fd:N --- TODO | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'TODO') diff --git a/TODO b/TODO index 10faf2d4..d23fd486 100644 --- a/TODO +++ b/TODO @@ -620,3 +620,23 @@ TMPDIR should be checked to ensure that we won't run out of space during the conversion, since current behaviour is very bad when this happens (it usually causes virt-sparsify to hang). This requires writing a small C binding to statvfs for OCaml. + +Passing file descriptors using attach-method fd:N +------------------------------------------------- + +The idea is that you can pass a file descriptor to the appliance to +another process, which can then attach to it by setting +'attach-method' to 'fd:N' (where N = file descriptor). + +The process(es) cooperating like this would have to arrange for mutual +exclusion on the file descriptor, since the protocol itself does not +and cannot support this. + +One issue with this is whether just passing the fd is sufficient, or +if other fields in the guestfs_h struct need to be passed too. +Another issue is that the parent process still has to handle +verbose/debug messages, and has to remain around to regain and kill +off the appliance at the end. Thus the parent cannot do much more +than wait(2) and at the same time select(2) on g->fd. + +Virt tools would have to have a new --attach-fd=N option. -- cgit