avc_netlink_loop(3)					     SELinux API documentation					       avc_netlink_loop(3)

NAME

       avc_netlink_open,  avc_netlink_close,  avc_netlink_acquire_fd,  avc_netlink_release_fd,	avc_netlink_check_nb,  avc_netlink_loop  - SELinux
       netlink processing.

SYNOPSIS

       #include <selinux/selinux.h>

       #include <selinux/avc.h>

       int avc_netlink_open(int blocking);

       void avc_netlink_close(void);

       int avc_netlink_acquire_fd(void);

       void avc_netlink_release_fd(void);

       void avc_netlink_loop(void);

       int avc_netlink_check_nb(void);

DESCRIPTION

       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 exam-
       ple 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  auto-
       matically 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 block.

       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 is closed.

RETURN VALUE

       avc_netlink_acquire_fd  returns	a non-negative file descriptor number on success.  Other functions with a return value return zero on suc-
       cess.  On error, -1 is returned and errno is set appropriately.

SEE ALSO

       avc_open(3), selinux_set_callback(3), selinux(8)

								    30 Mar 2009 					       avc_netlink_loop(3)