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diff --git a/man3p/pthread_rwlock_init.3p b/man3p/pthread_rwlock_init.3p new file mode 100644 index 000000000..f2fe880d3 --- /dev/null +++ b/man3p/pthread_rwlock_init.3p @@ -0,0 +1,137 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "PTHREAD_RWLOCK_DESTROY" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" pthread_rwlock_destroy +.SH NAME +pthread_rwlock_destroy, pthread_rwlock_init \- destroy and initialize +a read\-write lock object +.SH SYNOPSIS +.LP +\fB#include <pthread.h> +.br +.sp +int pthread_rwlock_destroy(pthread_rwlock_t *\fP\fIrwlock\fP\fB); +.br +int pthread_rwlock_init(pthread_rwlock_t *restrict\fP \fIrwlock\fP\fB, +.br +\ \ \ \ \ \ const pthread_rwlockattr_t *restrict\fP \fIattr\fP\fB); +\fP +\fB +.br +\fP +.SH DESCRIPTION +.LP +The \fIpthread_rwlock_destroy\fP() function shall destroy the read-write +lock object referenced by \fIrwlock\fP and release +any resources used by the lock. The effect of subsequent use of the +lock is undefined until the lock is reinitialized by another +call to \fIpthread_rwlock_init\fP(). An implementation may cause \fIpthread_rwlock_destroy\fP() +to set the object referenced by +\fIrwlock\fP to an invalid value. Results are undefined if \fIpthread_rwlock_destroy\fP() +is called when any thread holds +\fIrwlock\fP. Attempting to destroy an uninitialized read-write lock +results in undefined behavior. +.LP +The \fIpthread_rwlock_init\fP() function shall allocate any resources +required to use the read-write lock referenced by +\fIrwlock\fP and initializes the lock to an unlocked state with attributes +referenced by \fIattr\fP. If \fIattr\fP is NULL, the +default read-write lock attributes shall be used; the effect is the +same as passing the address of a default read-write lock +attributes object. Once initialized, the lock can be used any number +of times without being reinitialized. Results are undefined if +\fIpthread_rwlock_init\fP() is called specifying an already initialized +read-write lock. Results are undefined if a read-write +lock is used without first being initialized. +.LP +If the \fIpthread_rwlock_init\fP() function fails, \fIrwlock\fP shall +not be initialized and the contents of \fIrwlock\fP are +undefined. +.LP +Only the object referenced by \fIrwlock\fP may be used for performing +synchronization. The result of referring to copies of +that object in calls to \fIpthread_rwlock_destroy\fP(), \fIpthread_rwlock_rdlock\fP(), +\fIpthread_rwlock_timedrdlock\fP(), \fIpthread_rwlock_timedwrlock\fP(), +\fIpthread_rwlock_tryrdlock\fP(), \fIpthread_rwlock_trywrlock\fP(), +\fIpthread_rwlock_unlock\fP(), or \fIpthread_rwlock_wrlock\fP() is +undefined. +.SH RETURN VALUE +.LP +If successful, the \fIpthread_rwlock_destroy\fP() and \fIpthread_rwlock_init\fP() +functions shall return zero; otherwise, an +error number shall be returned to indicate the error. +.LP +The [EBUSY] and [EINVAL] error checks, if implemented, act as if they +were performed immediately at the beginning of processing +for the function and caused an error return prior to modifying the +state of the read-write lock specified by \fIrwlock\fP. +.SH ERRORS +.LP +The \fIpthread_rwlock_destroy\fP() function may fail if: +.TP 7 +.B EBUSY +The implementation has detected an attempt to destroy the object referenced +by \fIrwlock\fP while it is locked. +.TP 7 +.B EINVAL +The value specified by \fIrwlock\fP is invalid. +.sp +.LP +The \fIpthread_rwlock_init\fP() function shall fail if: +.TP 7 +.B EAGAIN +The system lacked the necessary resources (other than memory) to initialize +another read-write lock. +.TP 7 +.B ENOMEM +Insufficient memory exists to initialize the read-write lock. +.TP 7 +.B EPERM +The caller does not have the privilege to perform the operation. +.sp +.LP +The \fIpthread_rwlock_init\fP() function may fail if: +.TP 7 +.B EBUSY +The implementation has detected an attempt to reinitialize the object +referenced by \fIrwlock\fP, a previously initialized but +not yet destroyed read-write lock. +.TP 7 +.B EINVAL +The value specified by \fIattr\fP is invalid. +.sp +.LP +These functions shall not return an error code of [EINTR]. +.LP +\fIThe following sections are informative.\fP +.SH EXAMPLES +.LP +None. +.SH APPLICATION USAGE +.LP +Applications using these and related read-write lock functions may +be subject to priority inversion, as discussed in the Base +Definitions volume of IEEE\ Std\ 1003.1-2001, Section 3.285, Priority +Inversion. +.SH RATIONALE +.LP +None. +.SH FUTURE DIRECTIONS +.LP +None. +.SH SEE ALSO +.LP +\fIpthread_rwlock_rdlock\fP() , \fIpthread_rwlock_timedrdlock\fP() +, \fIpthread_rwlock_timedwrlock\fP() , \fIpthread_rwlock_tryrdlock\fP() +, \fIpthread_rwlock_trywrlock\fP() , \fIpthread_rwlock_unlock\fP() +, \fIpthread_rwlock_wrlock\fP() , the Base Definitions volume of IEEE\ Std\ 1003.1-2001, +\fI<pthread.h>\fP +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. In the +event of any discrepancy between this version and the original IEEE and +The Open Group Standard, the original IEEE and The Open Group Standard +is the referee document. The original Standard can be obtained online at +http://www.opengroup.org/unix/online.html . |