On Tue, Aug 14, 2018 at 09:18:26AM -0400, Edward Diener wrote: > I would like to use the libmount library to track end-user mount/umount > commands. My first question regards the use of the monitor. What is the > difference between userspace monitoring and kernel VFS monitoring ? The userspace handler also monitor writes to /run/mount/utab, it's important for options like user= or some NFS options maintained in userspace only. Anyway, if do you not care about options than it's probably enough to monitor VFS. The userspace monitor has been mostly implemented for systemd where is required to have information about all options, for more details see https://github.com/systemd/systemd/blob/master/src/core/mount.c#L1701 See also test program in the code: https://github.com/karelzak/util-linux/blob/master/libmount/src/monitor.c#L823 The another possibility to monitor VFS is to use directly poll() for /proc/self/mountinfo and than mnt_new_tabdiff(), see findmnt --poll: https://github.com/karelzak/util-linux/blob/master/misc-utils/findmnt.c#L1071 In this case you do not need the mnt_new_monitor(), but libmnt_monitor is probably better for complex things and epoll(). Karel -- Karel Zak <kzak@xxxxxxxxxx> http://karelzak.blogspot.com
