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Diffstat (limited to 'man3p/pthread_rwlock_unlock.3p')
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diff --git a/man3p/pthread_rwlock_unlock.3p b/man3p/pthread_rwlock_unlock.3p new file mode 100644 index 000000000..55b327363 --- /dev/null +++ b/man3p/pthread_rwlock_unlock.3p @@ -0,0 +1,95 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "PTHREAD_RWLOCK_UNLOCK" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" pthread_rwlock_unlock +.SH NAME +pthread_rwlock_unlock \- unlock a read-write lock object +.SH SYNOPSIS +.LP +\fB#include <pthread.h> +.br +.sp +int pthread_rwlock_unlock(pthread_rwlock_t\fP \fI*rwlock\fP\fB); \fP +\fB +.br +\fP +.SH DESCRIPTION +.LP +The \fIpthread_rwlock_unlock\fP() function shall release a lock held +on the read-write lock object referenced by \fIrwlock\fP. +Results are undefined if the read-write lock \fIrwlock\fP is not held +by the calling thread. +.LP +If this function is called to release a read lock from the read-write +lock object and there are other read locks currently held +on this read-write lock object, the read-write lock object remains +in the read locked state. If this function releases the last +read lock for this read-write lock object, the read-write lock object +shall be put in the unlocked state with no owners. +.LP +If this function is called to release a write lock for this read-write +lock object, the read-write lock object shall be put in +the unlocked state. +.LP +If there are threads blocked on the lock when it becomes available, +the scheduling policy shall determine which thread(s) shall +acquire the lock. \ If the Thread Execution Scheduling option is +supported, when threads executing with the +scheduling policies SCHED_FIFO, SCHED_RR, or SCHED_SPORADIC are waiting +on the lock, they shall acquire the lock in priority order +when the lock becomes available. For equal priority threads, write +locks shall take precedence over read locks. If the Thread Execution +Scheduling option is not supported, it is +implementation-defined whether write locks take precedence over read +locks. +.LP +Results are undefined if any of these functions are called with an +uninitialized read-write lock. +.SH RETURN VALUE +.LP +If successful, the \fIpthread_rwlock_unlock\fP() function shall return +zero; otherwise, an error number shall be returned to +indicate the error. +.SH ERRORS +.LP +The \fIpthread_rwlock_unlock\fP() function may fail if: +.TP 7 +.B EINVAL +The value specified by \fIrwlock\fP does not refer to an initialized +read-write lock object. +.TP 7 +.B EPERM +The current thread does not hold a lock on the read-write lock. +.sp +.LP +The \fIpthread_rwlock_unlock\fP() function shall not return an error +code of [EINTR]. +.LP +\fIThe following sections are informative.\fP +.SH EXAMPLES +.LP +None. +.SH APPLICATION USAGE +.LP +None. +.SH RATIONALE +.LP +None. +.SH FUTURE DIRECTIONS +.LP +None. +.SH SEE ALSO +.LP +\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_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 . |