lock.9: fix incorrect descriptions of LK_SHARED and LK_DOWNGRADE behavior

Reviewed by:	attilio
MFC after:	5 days
X-MFC after:	r243900
This commit is contained in:
Andriy Gapon 2012-12-23 12:56:04 +00:00
parent d8f9490c67
commit c858f5cebd

View File

@ -148,7 +148,9 @@ Flags indicating what action is to be taken.
.Bl -tag -width ".Dv LK_CANRECURSE"
.It Dv LK_SHARED
Acquire a shared lock.
If an exclusive lock is currently held, it will be downgraded.
If an exclusive lock is currently held,
.Dv EDEADLK
will be returned.
.It Dv LK_EXCLUSIVE
Acquire an exclusive lock.
If an exclusive lock is already held, and
@ -158,7 +160,8 @@ is not set, the system will
.It Dv LK_DOWNGRADE
Downgrade exclusive lock to a shared lock.
Downgrading a shared lock is not permitted.
If an exclusive lock has been recursed, all references will be downgraded.
If an exclusive lock has been recursed, the system will
.Xr panic 9 .
.It Dv LK_UPGRADE
Upgrade a shared lock to an exclusive lock.
If this call fails, the shared lock is lost.