MNT_EXPIRE(since Linux 2.6.8)
Mark the mount point as expired. If a mount point is not currently in use, then an initial call to
umount2()with this flag fails with the error
EAGAIN, but marks the mount point as expired. The mount point remains expired as long as it isn't accessed by any process. A second
MNT_EXPIREunmounts an expired mount point. This flag cannot be specified with either
What is the use-case for
MNT_EXPIRE? How is it useful?
What is different about an "expired" mount point?