These functions enable applications to handle notification of SELinux
events via netlink. The userspace AVC normally checks for netlink
messages on each call to avc_has_perm(3). Applications may wish to
override this behavior and check for notification separately, for
example in a select(2) loop. These functions also permit netlink
monitoring without requiring a call to avc_open(3).
avc_netlink_open() opens a netlink socket to receive SELinux
notifications. The socket descriptor is stored internally; use
avc_netlink_acquire_fd(3) to take ownership of it in application
code. The blocking argument controls whether the O_NONBLOCK flag is
set on the socket descriptor. avc_open(3) calls this function
internally, specifying non-blocking behavior.
avc_netlink_close() closes the netlink socket. This function is
called automatically by avc_destroy(3).
avc_netlink_acquire_fd() returns the netlink socket descriptor number
and informs the userspace AVC not to check the socket descriptor
automatically on calls to avc_has_perm(3).
avc_netlink_release_fd() returns control of the netlink socket to the
userspace AVC, re-enabling automatic processing of notifications.
avc_netlink_check_nb() checks the netlink socket for pending messages
and processes them. Callbacks for policyload and enforcing changes
will be called; see selinux_set_callback(3). This function does not
avc_netlink_loop() enters a loop blocking on the netlink socket and
processing messages as they are received. This function will not
return unless an error occurs on the socket, in which case the socket
This page is part of the selinux (Security-Enhanced Linux user-space
libraries and tools) project. Information about the project can be
found at ⟨https://github.com/SELinuxProject/selinux/wiki⟩. If you
have a bug report for this manual page, see
page was obtained from the project's upstream Git repository
⟨https://github.com/SELinuxProject/selinux⟩ on 2020-06-09. (At that
time, the date of the most recent commit that was found in the repos‐
itory was 2020-06-04.) If you discover any rendering problems in
this HTML version of the page, or you believe there is a better or
more up-to-date source for the page, or you have corrections or
improvements to the information in this COLOPHON (which is not part
of the original manual page), send a mail to email@example.com
30 Mar 2009 avc_netlink_loop(3)