[RFC PATCH 07/14] Add sample notification program [ver #3]

[Guenter Roeck]

On Wed, Jan 15, 2020 at 01:31:38PM +0000, David Howells wrote:
> The sample program is run like:
> 
> 	./samples/watch_queue/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
> 
> producing:
> 
> 	# ./watch_test
> 	read() = 16
> 	NOTIFY[000]: ty=000001 sy=02 i=00000110
> 	KEY 2ffc2e5d change=2[linked] aux=1035096409
> 	read() = 16
> 	NOTIFY[000]: ty=000001 sy=02 i=00000110
> 	KEY 2ffc2e5d change=3[unlinked] aux=1035096409
> 
> Other events may be produced, such as with a failing disk:
> 
> 	read() = 22
> 	NOTIFY[000]: ty=000003 sy=02 i=00000416
> 	USB 3-7.7 dev-reset e=0 r=0
> 	read() = 24
> 	NOTIFY[000]: ty=000002 sy=06 i=00000418
> 	BLOCK 00800050 e=6[critical medium] s=64000ef8
> 
> This corresponds to:
> 
> 	blk_update_request: critical medium error, dev sdf, sector 1677725432 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 0
> 
> in dmesg.
> 
> Signed-off-by: David Howells <dhowells at redhat.com>

mips:allmodconfig:

samples/watch_queue/watch_test.c: In function ‘keyctl_watch_key’:
samples/watch_queue/watch_test.c:34:17: error: ‘__NR_keyctl’ undeclared

Guenter