pthread

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• 網(wǎng)絡(luò)線程示例；條件變量主要操作；線程模型

例句

I further tested this simple Pthread code on the PPE to see how it scales with an increasing number of threads.

我在PPE上進(jìn)一步測(cè)試了這個(gè)簡(jiǎn)單的Pthread代碼，以此了解隨著線程數(shù)量的增加它的性能變化情況。

As you can see, pthread_mutex_init accepts a pointer to an already-allocated region of memory to initialize as a mutex.

正如所示，pthread_mutex_init接受一個(gè)指針作為參數(shù)以初始化為互斥對(duì)象，該指針指向一塊已分配好的內(nèi)存區(qū)。

In other words, the system allocates at least 10MB of private storage for each pthread.

換言之，系統(tǒng)為每個(gè)pthread分配至少10MB的專用存儲(chǔ)。

This sounds a bit confusing, but the pthread example below will clarify how condition variables work.

這聽起來有點(diǎn)難以理解，下面的pthread例子會(huì)說明條件變量是怎么工作的。

Thus, PTHREAD_PROCESS_SHARED and interprocess POSIX synchronization primitives can be implemented and are now available.

這樣，PTHREAD_PROCESS_SHARED和進(jìn)程間POSIX同步原語可以被實(shí)現(xiàn)，而且現(xiàn)在可用。

pthread -qthreaded or _r invocation mode Creates programs running in a multithreaded environment.

pthread-qthreaded或_r調(diào)用模式創(chuàng)建在多線程環(huán)境中運(yùn)行的程序

In Linux, pthread_cond_signal wakes up a thread waiting on a conditional variable.

在Linux中，pthread_cond_signal會(huì)喚醒等待某個(gè)條件變更的某個(gè)線程。

Futex (fast user space mutex) is done by the kernel on the thread ID upon pthread_join (for more on futex, please see Resources).

當(dāng)pthread_join發(fā)生時(shí)由內(nèi)核根據(jù)線程ID來完成Futex（fastuserspacemutex）。（要了解futex的更多信息，請(qǐng)參閱參考資料）。

POSIX provides locking and synchronization support through the pthread_mutex data type.

POSIX通過pthread_mutex數(shù)據(jù)類型提供鎖定和同步支持。

In Linux, the pthread_cancel method terminates execution of the thread identified by the specified threadId.

在Linux中，pthread_cancel可以終止由具體的threadId所標(biāo)識(shí)的線程的執(zhí)行。

Note that you've invoked pthread_cond_broadcast after releasing the mutex.

注意，在釋放互斥鎖之后調(diào)用pthread_cond_broadcast。

If the list were originally empty, you call pthread_cond_broadcast to post push data into the list.

如果列表原來是空的，就調(diào)用pthread_cond_broadcast以宣告列表中已經(jīng)添加了數(shù)據(jù)。

In libspe2, the operation is synchronous, so if you want to run a thread in the background, you have to make your own pthread calls.

在libspe2中，這個(gè)操作變成同步的了，因此您可能會(huì)希望在后臺(tái)運(yùn)行一個(gè)線程，并發(fā)出自己的pthread調(diào)用。

A POSIX API for creating a pthread_mutex lets the mutex implement the priority-inheritance protocol.

用于創(chuàng)建pthread_mutex的POSIXAPI使用互斥鎖來實(shí)現(xiàn)優(yōu)先級(jí)繼承協(xié)議。

If you need to block the calling thread for a specific time, then use the pthread_cond_timewait to block the thread.

如果您需要在指定的一段時(shí)間內(nèi)阻塞發(fā)出調(diào)用的線程，那么請(qǐng)使用pthread_cond_timewait來阻塞它。

pthread_mutexes can be created with different locking policies.

pthread_mutex可以使用不同的鎖定策略創(chuàng)建。

pthread_rwlock_rdlock may fail if the maximum number of read locks (implementation defined) for the lock has been exceeded.

如果超過了最大讀鎖數(shù)量（由實(shí)現(xiàn)定義），pthread_rwlock_rdlock可能會(huì)失敗。

This careful Pthread scheduling leads to much more deterministic and repeatable test runs.

這種仔細(xì)的Pthread調(diào)度方法使測(cè)試運(yùn)行的結(jié)果更加準(zhǔn)確，可重復(fù)性更高。

Table 1 above displays the pthread condition variable for synchronization between threads.

前面的表1給出了用于線程間同步的pthread條件變量。

You can further optimize this situation by using pthread_mutex_timedlock API, if your system supports it (see Resources).

如果系統(tǒng)支持的話，可以使用pthread_mutex_timedlockAPI進(jìn)一步優(yōu)化這個(gè)場(chǎng)景（見參考資料）。

Instead of providing an abstraction of logical SPUs, this interface is thread-oriented and behaves in a similar way to the pthread library.

這個(gè)接口并不是提供一個(gè)邏輯SPU的抽象，而是面向線程的，它的工作方式與pthread庫類似。

The linker complained of some missing pthreads-related exports.

鏈接器抱怨缺少與pthread相關(guān)的輸出。

Otherwise, it can be created statically when it is declared by a pthread_mutex_t variable.

或者，當(dāng)通過pthread_mutex_t變量聲明它的時(shí)候，可以靜態(tài)地創(chuàng)建它。

Meanwhile, you can use pthread_xxxx calls at any time after the thread has been created.

同時(shí)，您在創(chuàng)建線程之后的任意時(shí)候都可以使用pthread_xxxx。

Linux pthread mutexes are supported by fast user-space mutexes, known as futexes.

快速用戶空間互斥（也被稱為futexes）支持Linuxpthread互斥鎖。

Immediately after unlocking the mutex, thread 2 calls the function pthread_cond_broadcast(&mycond).

在對(duì)互斥對(duì)象解鎖之后，2號(hào)線程會(huì)立即調(diào)用函數(shù)pthread_cond_broadcast（&mycond）。

With this background, let's look at the function pthread_cond_timedwait, which you use for the second check.

有了這些背景知識(shí)，我們來看看pthread_cond_timedwait函數(shù)，這個(gè)函數(shù)用于進(jìn)行第二個(gè)檢查。

While still holding the mutex lock, our thread will call pthread_cond_wait(&mycond, &mymutex).

鎖定互斥對(duì)象時(shí)，線程將調(diào)用pthread_cond_wait（&mycond，&mymutex）。

Take care to invoke pthread_rwlock_unlock n times if there are n concurrent read locks for the lock.

如果有n個(gè)并發(fā)的讀鎖，一定要調(diào)用pthread_rwlock_unlockn次。

The POSIX lock type is a pthread_mutex.

POSIX鎖的類型為pthread_mutex。

If the reader thread is awakened before the timeout, the return value from pthread_cond_timedwait will be 0.

如果在超時(shí)之前讀線程被喚醒，pthread_cond_timedwait的返回值是0。

As a second argument, it can also accept an optional pthread_mutexattr_t pointer.

第二個(gè)參數(shù)，可以接受一個(gè)可選的pthread_mutexattr_t指針。

A note on Pthreads scheduling and compiler optimization

關(guān)于Pthread調(diào)度和編譯器優(yōu)化的幾點(diǎn)說明