Re: [libvirt] PATCH: Allow specific FDs to be kept open in virExec()

With my recent patches to virExec(), all FDs except stdin/out/err are closed before the child is exec'd to prevent accidental leaks. Of course I forgot the one key place where we need to propagate FDs... The TAP devices passed to QEMU. This patch adds a 'keepfd' parameter to virExec() which allows the caller to specify a bitset of file descriptors to keep open, and updates the callers to use this as required. The QEMU driver specifies any TAP fds and the LXC driver specifies its PTY this way removing a previous hack.