xref: /illumos-gate/usr/src/man/man3c/plock.3c (revision b49b27dcb66b2c7f4a23f7bc158e2dde5cd79030)
te
Copyright 1989 AT&T. Copyright (c) 2004, Sun Microsystems, Inc. All Rights Reserved.
The contents of this file are subject to the terms of the Common Development and Distribution License (the "License"). You may not use this file except in compliance with the License.
You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing. See the License for the specific language governing permissions and limitations under the License.
When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
PLOCK 3C "Mar 22, 2004"
NAME
plock - lock or unlock into memory process, text, or data
SYNOPSIS

#include <sys/lock.h>

int plock(int op);
DESCRIPTION

The plock() function allows the calling process to lock or unlock into memory its text segment (text lock), its data segment (data lock), or both its text and data segments (process lock). Locked segments are immune to all routine swapping. The effective user ID of the calling process must be super-user to use this call.

The plock() function performs the function specified by op: PROCLOCK

Lock text and data segments into memory (process lock).

TXTLOCK

Lock text segment into memory (text lock).

DATLOCK

Lock data segment into memory (data lock).

UNLOCK

Remove locks.

RETURN VALUES

Upon successful completion, 0 is returned. Otherwise, -1 is returned and errno is set to indicate the error.

ERRORS

The plock() function fails and does not perform the requested operation if: EAGAIN

Not enough memory.

EINVAL

The op argument is equal to PROCLOCK and a process lock, a text lock, or a data lock already exists on the calling process; the op argument is equal to TXTLOCK and a text lock or a process lock already exists on the calling process; the op argument is equal to DATLOCK and a data lock or a process lock already exists on the calling process; or the op argument is equal to UNLOCK and no lock exists on the calling process.

EPERM

The {PRIV_PROC_LOCK_MEMORY} privilege is not asserted in the effective set of the calling process.

USAGE

The mlock(3C) and mlockall(3C) functions are the preferred interfaces for process locking.

ATTRIBUTES

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE
MT-Level MT-Safe
SEE ALSO

exec(2), exit(2), fork(2), memcntl(2), mlock(3C), mlockall(3C), attributes(5)