tree f3ac1e1e60e310546be242ed0d4a906ff73f7b50
parent 92074236c8092adf6f8ddb262f71054bed9dc5ad
author David Howells <dhowells@redhat.com> 1559916801 +0100
committer David Howells <dhowells@redhat.com> 1562317922 +0100

Add sample notification program

This needs to be linked with -lkeyutils.

It is run like:

	./watch_test

and watches "/" for mount changes and the current session keyring for key
changes:

	# keyctl add user a a @s
	1035096409
	# keyctl unlink 1035096409 @s
	# mount -t tmpfs none /mnt/nfsv3tcp/
	# umount /mnt/nfsv3tcp

producing:

	# ./watch_test
	ptrs h=4 t=2 m=20003
	NOTIFY[00000004-00000002] ty=0003 sy=0002 i=01000010
	KEY 2ffc2e5d change=2[linked] aux=1035096409
	ptrs h=6 t=4 m=20003
	NOTIFY[00000006-00000004] ty=0003 sy=0003 i=01000010
	KEY 2ffc2e5d change=3[unlinked] aux=1035096409
	ptrs h=8 t=6 m=20003
	NOTIFY[00000008-00000006] ty=0001 sy=0000 i=02000010
	MOUNT 00000013 change=0[new_mount] aux=168
	ptrs h=a t=8 m=20003
	NOTIFY[0000000a-00000008] ty=0001 sy=0001 i=02000010
	MOUNT 00000013 change=1[unmount] aux=168

Other events may be produced, such as with a failing disk:

	ptrs h=5 t=2 m=6000004
	NOTIFY[00000005-00000002] ty=0004 sy=0006 i=04000018
	BLOCK 00800050 e=6[critical medium] s=5be8

This corresponds to:

	print_req_error: critical medium error, dev sdf, sector 23528 flags 0

in dmesg.

Signed-off-by: David Howells <dhowells@redhat.com>