lock_try_read(9r) lock_try_read(9r)
NAME
lock_try_read - General: Tries to assert a complex lock with read-only access
SYNOPSIS
#include <kern/lock.h>
boolean_t lock_try_read(
lock_t lock_structptr );
ARGUMENTS
Specifies a pointer to the complex lock structure, lock. This is the lock structure associated with the resource on which you want to try
to assert a complex lock with read-only access. The lock structure is an opaque data structure; that is, its associated members are refer-
enced and manipulated by the operating system and not by the user of the complex lock mechanism.
DESCRIPTION
The lock_try_read routine tries to assert a complex lock (without blocking) with read-only access for the resource associated with the
specified lock structure pointer. To release a complex lock with read-only access successfully asserted by lock_try_read, call the
lock_done routine.
NOTES
You must call lock_init (once only) prior to calling lock_try_read to initialize the lock structure pointer for the resource. A resource,
from the kernel module's standpoint, is data that more than one kernel thread can manipulate. You can store the resource in global vari-
ables and in data structure members.
RETURN VALUES
The lock_try_read routine returns one of the following values: The attempt to acquire the read-only complex lock was successful. The
attempt to acquire the read-only complex lock was unsuccessful.
FILES
SEE ALSO
Routines: lock_done(9r), lock_terminate(9r), lock_try_write(9r), lock_write(9r)
Data Structures: lock(9s)
lock_try_read(9r)
