You can use the same channels in PHP for input, standard output, and output to the error channel, respectively.

您可以将php中的相同通道分别用于输入、标准输出和输出到错误通道。

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That is, a channel guard is ready if and only if the process at the other end of the channel has output to it and this data has not yet been input by this process.

也就是说，只有在通道另一端的进程已经输出数据，而该数据还没有被进程输入的时候，警卫才就绪。

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A process associates its input or output channel file descriptors (sockets) with a port number and an IP address, a process known as binding, to send and receive data via the network.

进程会与它输入或输出频道文件的描述符(套接口)联系在一个端口号，IP地址，已知的捆绑的进程上，从而通过网络发送和接受数据。

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