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4327 rwlock(3c): Formatting issues and typos
*** 1,22 ****
'\" te
.\" Copyright (c) 1998 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]
! .TH RWLOCK 3C "May 14, 1998"
.SH NAME
rwlock, rwlock_init, rwlock_destroy, rw_rdlock, rw_wrlock, rw_tryrdlock,
rw_trywrlock, rw_unlock \- multiple readers, single writer locks
.SH SYNOPSIS
.LP
.nf
cc -mt [ \fIflag\fR... ] \fIfile\fR...[ \fIlibrary\fR... ]
#include <synch.h>
! \fBint\fR \fBrwlock_init\fR(\fBrwlock_t *\fR\fIrwlp\fR, \fBint\fR \fItype\fR, \fBvoid *\fR \fIarg\fR);
.fi
.LP
.nf
\fBint\fR \fBrwlock_destroy\fR(\fBrwlock_t *\fR\fIrwlp\fR);
--- 1,22 ----
'\" te
.\" Copyright (c) 1998 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]
! .TH RWLOCK 3C "Dec 19, 2013"
.SH NAME
rwlock, rwlock_init, rwlock_destroy, rw_rdlock, rw_wrlock, rw_tryrdlock,
rw_trywrlock, rw_unlock \- multiple readers, single writer locks
.SH SYNOPSIS
.LP
.nf
cc -mt [ \fIflag\fR... ] \fIfile\fR...[ \fIlibrary\fR... ]
#include <synch.h>
! \fBint\fR \fBrwlock_init\fR(\fBrwlock_t *\fR\fIrwlp\fR, \fBint\fR \fItype\fR, \fBvoid *\fR\fIarg\fR);
.fi
.LP
.nf
\fBint\fR \fBrwlock_destroy\fR(\fBrwlock_t *\fR\fIrwlp\fR);
*** 61,73 ****
cooperating processes (see \fBmmap\fR(2)), and are initialized for this
purpose.
.sp
.LP
Additionally, readers/writer locks must be initialized prior to use.
! \fBrwlock_init()\fR The readers/writer lock pointed to by \fIrwlp\fR is
initialized by \fBrwlock_init()\fR. A readers/writer lock is capable of having
! several types of behavior, which is specified by \fBtype\fR. \fIarg\fR is
currently not used, although a future type may define new behavior parameters
by way of \fIarg\fR.
.sp
.LP
The \fItype\fR argument can be one of the following:
--- 61,73 ----
cooperating processes (see \fBmmap\fR(2)), and are initialized for this
purpose.
.sp
.LP
Additionally, readers/writer locks must be initialized prior to use.
! The readers/writer lock pointed to by \fIrwlp\fR is
initialized by \fBrwlock_init()\fR. A readers/writer lock is capable of having
! several types of behavior, which is specified by \fItype\fR. \fIarg\fR is
currently not used, although a future type may define new behavior parameters
by way of \fIarg\fR.
.sp
.LP
The \fItype\fR argument can be one of the following:
*** 97,107 ****
.RE
.sp
.LP
Additionally, readers/writer locks can be initialized by allocation in zeroed
! memory. A \fBtype\fR of \fBUSYNC_THREAD\fR is assumed in this case. Multiple
threads must not simultaneously initialize the same readers/writer lock. And a
readers/writer lock must not be re-initialized while in use by other threads.
.sp
.LP
The following are default readers/writer lock initialization (intra-process):
--- 97,107 ----
.RE
.sp
.LP
Additionally, readers/writer locks can be initialized by allocation in zeroed
! memory. A \fItype\fR of \fBUSYNC_THREAD\fR is assumed in this case. Multiple
threads must not simultaneously initialize the same readers/writer lock. And a
readers/writer lock must not be re-initialized while in use by other threads.
.sp
.LP
The following are default readers/writer lock initialization (intra-process):
*** 156,166 ****
\fIrwlp\fR. If the readers/writer lock is currently locked for writing, the
calling thread blocks until the write lock is freed. Multiple threads may
simultaneously hold a read lock on a readers/writer lock.
.sp
.LP
! \fBrw_tryrdlock()\fR trys to get a read lock on the readers/writer lock pointed
to by \fIrwlp\fR. If the readers/writer lock is locked for writing, it returns
an error; otherwise, the read lock is acquired.
.sp
.LP
\fBrw_wrlock()\fR gets a write lock on the readers/writer lock pointed to by
--- 156,166 ----
\fIrwlp\fR. If the readers/writer lock is currently locked for writing, the
calling thread blocks until the write lock is freed. Multiple threads may
simultaneously hold a read lock on a readers/writer lock.
.sp
.LP
! \fBrw_tryrdlock()\fR tries to get a read lock on the readers/writer lock pointed
to by \fIrwlp\fR. If the readers/writer lock is locked for writing, it returns
an error; otherwise, the read lock is acquired.
.sp
.LP
\fBrw_wrlock()\fR gets a write lock on the readers/writer lock pointed to by
*** 168,186 ****
writing, the calling thread blocks until all the read and write locks are
freed. At any given time, only one thread may have a write lock on a
readers/writer lock.
.sp
.LP
! \fBrw_trywrlock()\fR trys to get a write lock on the readers/writer lock
pointed to by \fIrwlp\fR. If the readers/writer lock is currently locked for
reading or writing, it returns an error.
.sp
.LP
\fBrw_unlock()\fR unlocks a readers/writer lock pointed to by \fIrwlp\fR, if
the readers/writer lock is locked and the calling thread holds the lock for
either reading or writing. One of the other threads that is waiting for the
! readers/writer lock to be freed will be unblocked, provided there is other
waiting threads. If the calling thread does not hold the lock for either
reading or writing, no error status is returned, and the program's behavior is
unknown.
.SH RETURN VALUES
.sp
--- 168,186 ----
writing, the calling thread blocks until all the read and write locks are
freed. At any given time, only one thread may have a write lock on a
readers/writer lock.
.sp
.LP
! \fBrw_trywrlock()\fR tries to get a write lock on the readers/writer lock
pointed to by \fIrwlp\fR. If the readers/writer lock is currently locked for
reading or writing, it returns an error.
.sp
.LP
\fBrw_unlock()\fR unlocks a readers/writer lock pointed to by \fIrwlp\fR, if
the readers/writer lock is locked and the calling thread holds the lock for
either reading or writing. One of the other threads that is waiting for the
! readers/writer lock to be freed will be unblocked, provided there are other
waiting threads. If the calling thread does not hold the lock for either
reading or writing, no error status is returned, and the program's behavior is
unknown.
.SH RETURN VALUES
.sp
*** 195,205 ****
.ne 2
.na
\fB\fBEINVAL\fR \fR
.ad
.RS 11n
! \fBtype\fR is invalid.
.RE
.sp
.LP
The \fBrw_tryrdlock()\fR or \fBrw_trywrlock()\fR functions will fail if:
--- 195,205 ----
.ne 2
.na
\fB\fBEINVAL\fR \fR
.ad
.RS 11n
! \fItype\fR is invalid.
.RE
.sp
.LP
The \fBrw_tryrdlock()\fR or \fBrw_trywrlock()\fR functions will fail if:
*** 207,217 ****
.ne 2
.na
\fB\fBEBUSY\fR \fR
.ad
.RS 10n
! The reader or writer lock pointed to by \fIrwlp\fR was already locked.
.RE
.sp
.LP
These functions may fail if:
--- 207,217 ----
.ne 2
.na
\fB\fBEBUSY\fR \fR
.ad
.RS 10n
! The readers/writer lock pointed to by \fIrwlp\fR was already locked.
.RE
.sp
.LP
These functions may fail if: