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diff --git a/static/freebsd/man3/pthread_rwlock_rdlock.3 3.html b/static/freebsd/man3/pthread_rwlock_rdlock.3 3.html new file mode 100644 index 00000000..a54dcdae --- /dev/null +++ b/static/freebsd/man3/pthread_rwlock_rdlock.3 3.html @@ -0,0 +1,119 @@ +<table class="head"> + <tr> + <td class="head-ltitle">PTHREAD_RWLOCK_RDLOCK(3)</td> + <td class="head-vol">Library Functions Manual</td> + <td class="head-rtitle">PTHREAD_RWLOCK_RDLOCK(3)</td> + </tr> +</table> +<div class="manual-text"> +<section class="Sh"> +<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1> +<p class="Pp"><code class="Nm">pthread_rwlock_rdlock</code>, + <code class="Nm">pthread_rwlock_tryrdlock</code> — + <span class="Nd">acquire a read/write lock for reading</span></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="LIBRARY"><a class="permalink" href="#LIBRARY">LIBRARY</a></h1> +<p class="Pp"><span class="Lb">POSIX Threads Library (libpthread, + -lpthread)</span></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> +<p class="Pp"><code class="In">#include + <<a class="In">pthread.h</a>></code></p> +<p class="Pp"><var class="Ft">int</var> + <br/> + <code class="Fn">pthread_rwlock_rdlock</code>(<var class="Fa" style="white-space: nowrap;">pthread_rwlock_t + *lock</var>);</p> +<p class="Pp"><var class="Ft">int</var> + <br/> + <code class="Fn">pthread_rwlock_tryrdlock</code>(<var class="Fa" style="white-space: nowrap;">pthread_rwlock_t + *lock</var>);</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> +<p class="Pp">The + <a class="permalink" href="#pthread_rwlock_rdlock"><code class="Fn" id="pthread_rwlock_rdlock">pthread_rwlock_rdlock</code></a>() + function acquires a read lock on <var class="Fa">lock</var> provided that + <var class="Fa">lock</var> is not presently held for writing and no writer + threads are presently blocked on the lock. If the read lock cannot be + immediately acquired, the calling thread blocks until it can acquire the + lock.</p> +<p class="Pp" id="pthread_rwlock_tryrdlock">The + <a class="permalink" href="#pthread_rwlock_tryrdlock"><code class="Fn">pthread_rwlock_tryrdlock</code></a>() + function performs the same action, but does not block if the lock cannot be + immediately obtained (i.e., the lock is held for writing or there are + waiting writers).</p> +<p class="Pp" id="pthread_rwlock_unlock">A thread may hold multiple concurrent + read locks. If so, + <a class="permalink" href="#pthread_rwlock_unlock"><code class="Fn">pthread_rwlock_unlock</code></a>() + must be called once for each lock obtained.</p> +<p class="Pp">The results of acquiring a read lock while the calling thread + holds a write lock are undefined.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="IMPLEMENTATION_NOTES"><a class="permalink" href="#IMPLEMENTATION_NOTES">IMPLEMENTATION + NOTES</a></h1> +<p class="Pp">To prevent writer starvation, writers are favored over + readers.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="RETURN_VALUES"><a class="permalink" href="#RETURN_VALUES">RETURN + VALUES</a></h1> +<p class="Pp">If successful, the <code class="Fn">pthread_rwlock_rdlock</code>() + and <code class="Fn">pthread_rwlock_tryrdlock</code>() functions will return + zero. Otherwise an error number will be returned to indicate the error.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="ERRORS"><a class="permalink" href="#ERRORS">ERRORS</a></h1> +<p class="Pp">The <code class="Fn">pthread_rwlock_tryrdlock</code>() function + will fail if:</p> +<dl class="Bl-tag"> + <dt id="EBUSY">[<a class="permalink" href="#EBUSY"><code class="Er">EBUSY</code></a>]</dt> + <dd>The lock could not be acquired because a writer holds the lock or was + blocked on it.</dd> +</dl> +<p class="Pp">The <code class="Fn">pthread_rwlock_rdlock</code>() and + <code class="Fn">pthread_rwlock_tryrdlock</code>() functions may fail + if:</p> +<dl class="Bl-tag"> + <dt id="EAGAIN">[<a class="permalink" href="#EAGAIN"><code class="Er">EAGAIN</code></a>]</dt> + <dd>The lock could not be acquired because the maximum number of read locks + against <var class="Fa">lock</var> has been exceeded.</dd> + <dt id="EDEADLK">[<a class="permalink" href="#EDEADLK"><code class="Er">EDEADLK</code></a>]</dt> + <dd>The current thread already owns <var class="Fa">lock</var> for + writing.</dd> + <dt id="EINVAL">[<a class="permalink" href="#EINVAL"><code class="Er">EINVAL</code></a>]</dt> + <dd>The value specified by <var class="Fa">lock</var> is invalid.</dd> + <dt id="ENOMEM">[<a class="permalink" href="#ENOMEM"><code class="Er">ENOMEM</code></a>]</dt> + <dd>Insufficient memory exists to initialize the lock (applies to statically + initialized locks only).</dd> +</dl> +</section> +<section class="Sh"> +<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE + ALSO</a></h1> +<p class="Pp"><a class="Xr">pthread_rwlock_init(3)</a>, + <a class="Xr">pthread_rwlock_trywrlock(3)</a>, + <a class="Xr">pthread_rwlock_unlock(3)</a>, + <a class="Xr">pthread_rwlock_wrlock(3)</a></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="STANDARDS"><a class="permalink" href="#STANDARDS">STANDARDS</a></h1> +<p class="Pp">The <code class="Fn">pthread_rwlock_rdlock</code>() and + <code class="Fn">pthread_rwlock_tryrdlock</code>() functions are expected to + conform to <span class="St">Version 2 of the Single UNIX + Specification (“SUSv2”)</span>.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1> +<p class="Pp">The <code class="Fn">pthread_rwlock_rdlock</code>() function first + appeared in <span class="Ux">FreeBSD 3.0</span>.</p> +</section> +</div> +<table class="foot"> + <tr> + <td class="foot-date">August 4, 1998</td> + <td class="foot-os">FreeBSD 15.0</td> + </tr> +</table> |