lock_read(9r)lock_read(9r)NAME
lock_read - General: Asserts a complex lock with read-only access
SYNOPSIS
#include <kern/lock.h>
void lock_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
assert a complex lock with read-only access. The lock structure is an opaque data structure; that is, its associated members are referenced
and manipulated by the operating system and not by the user of the complex lock mechanism.
DESCRIPTION
The lock_read routine asserts a lock with read-only access for the resource associated with the specified lock structure pointer. The
lock_read routine allows multiple kernel threads to access the resource read-only at the same time. When a read lock is asserted, the pro-
tected resource is guaranteed not to change.
To release a previously asserted read lock, call the lock_done routine.
NOTES
You must call lock_init (once only) prior to calling lock_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 variables and
in data structure members.
RETURN VALUES
None
FILES SEE ALSO
Routines: lock_done(9r), lock_terminate(9r), lock_try_read(9r), lock_try_write(9r), lock_write(9r)
Data Structures: lock(9s)lock_read(9r)
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lock_init(9r)lock_init(9r)NAME
lock_init - General: Initializes a complex lock
SYNOPSIS
#include <kern/lock.h>
void lock_init(
lock_t lock_structptr,
boolean_t can_sleep );
ARGUMENTS
Specifies a pointer to the complex lock structure, lock. The lock structure is an opaque data structure; that is, its associated members
are referenced and manipulated by the operating system and not by the user of the complex lock mechanism. Specifies a Boolean value that
indicates whether to allow kernel threads to block (sleep) if the complex lock is asserted. You can pass to this argument only the value
TRUE (allow kernel threads to block if the lock is asserted).
DESCRIPTION
The lock_init routine initializes a complex lock. You identify this lock by declaring a pointer to a complex lock structure and passing it
as the first argument. The complex lock structure pointer must be initialized before you can assert read and write operations on the com-
plex lock.
RETURN VALUES
None
FILES SEE ALSO
Routines: lock_done(9r), lock_read(9r), lock_terminate(9r), lock_try_read(9r), lock_try_write(9r), lock_write(9r)
Data Structures: lock(9s)lock_init(9r)
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Hi Everybody..
I am using Moblin V2 which has nautilus file manager the one which is also used in Ubuntu.
I want to lock the access to file system such that i can only browse my home folder not other locations like /, /usr, /bin and all.
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