問題描述

在 Windows 上，我遇到了在 Unix 上從未遇到過的問題.這就是讓線程休眠少于一毫秒的方法.在 Unix 上，您通常有多種選擇(sleep、usleep 和 nanosleep)來滿足您的需求.然而，在 Windows 上，只有 Sleep 以毫秒為粒度.

On Windows I have a problem I never encountered on Unix. That is how to get a thread to sleep for less than one millisecond. On Unix you typically have a number of choices (sleep, usleep and nanosleep) to fit your needs. On Windows, however, there is only Sleep with millisecond granularity.

在 Unix 上，我可以使用 select 系統(tǒng)調(diào)用來創(chuàng)建一個(gè)非常簡(jiǎn)單的微秒睡眠:

On Unix, I can use the use the select system call to create a microsecond sleep which is pretty straightforward:

int usleep(long usec)
{
    struct timeval tv;
    tv.tv_sec = usec/1000000L;
    tv.tv_usec = usec%1000000L;
    return select(0, 0, 0, 0, &tv);
}

如何在 Windows 上實(shí)現(xiàn)相同的效果?

How can I achieve the same on Windows?

推薦答案

在 Windows 上使用 select 強(qiáng)制您包含 Winsock 庫，它必須在您的應(yīng)用程序中像這樣初始化:

On Windows the use of select forces you to include the Winsock library which has to be initialized like this in your application:

WORD wVersionRequested = MAKEWORD(1,0);
WSADATA wsaData;
WSAStartup(wVersionRequested, &wsaData);

然后 select 將不允許在沒有任何套接字的情況下調(diào)用您，因此您必須做更多的事情來創(chuàng)建 microsleep 方法:

And then the select won't allow you to be called without any socket so you have to do a little more to create a microsleep method:

int usleep(long usec)
{
    struct timeval tv;
    fd_set dummy;
    SOCKET s = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
    FD_ZERO(&dummy);
    FD_SET(s, &dummy);
    tv.tv_sec = usec/1000000L;
    tv.tv_usec = usec%1000000L;
    return select(0, 0, 0, &dummy, &tv);
}

所有這些創(chuàng)建的 usleep 方法在成功時(shí)返回零，錯(cuò)誤時(shí)返回非零.

All these created usleep methods return zero when successful and non-zero for errors.

這篇關(guān)于如何在 Windows 上使線程休眠少于一毫秒的文章就介紹到這了，希望我們推薦的答案對(duì)大家有所幫助，也希望大家多多支持html5模板網(wǎng)！