无法从套接字读取（挂起） [英] Can't read from socket (hangs)

问题描述

编辑：对不起，不小心张贴了另一个问题的标题。已修复。

Sorry, accidentally posted with a title for a different question. Fixed.

嘿，

我使用PHP连接到本地C ++套接字服务器状态在一个Web应用程序和几个守护程序之间。我可以发送数据到套接字服务器，但不能从它接收;它只是阻塞在 socket_read（），并无限期挂起。我忘记了一些愚蠢的东西（比如NULL字符或换行符的不同组合）？ PHP如下：

I'm using PHP to connect to a local C++ socket server to keep state between a web app and a couple of daemons. I can send data to the socket server, but not receive from it; it just blocks on socket_read() and hangs indefinitely. Am I forgetting something dumb (like a NULL character or a different combination of newline characters)? The PHP is below:

socket_connect($sock, $addr, $port); 
socket_write($sock, 'Hello world');
$str = '';
while($resp = socket_read($sock, 1000))
    $str .= $resp;
socket_close($sock);
die("Server said: {$str}");

套接字服务器的相关部分如下（注意< 和>> 运算符重载）：

The related part of the socket server is below (note that the << and >> operators are overloaded):

std::string data;
sock >> data;
sock << data << std::endl;

其中>> c $ c> Socket :: recv（std :: string&）和>> 调用 Socket :: send（const std :: string&）。

Where >> calls Socket::recv(std::string&) and >> calls Socket::send(const std::string&).

这种方法适用于（例如）telnet，但PHP不想播放不错。

This works fine from (for example) telnet, but PHP doesn't want to play nice. Any thoughts/suggestions are appreciated.

推荐答案

PHP中的套接字在大多数编程语言中都默认在阻塞模式下打开，除非使用 socket_set_nonblock 设置。

Sockets in PHP, as in most programming languages, are opened in blocking mode by default, unless set otherwise using socket_set_nonblock.

这意味着除非发生超时/错误或接收到数据，否则<$

This means that unless a timeout/error occurs or data is received, socket_read will hang there forever.

由于您的终止字符似乎是一个新行，请尝试：

Since your termination character seems to be a new line, try that:

while($resp = socket_read($sock, 1000)) {
   $str .= $resp;
   if (strpos($str, "\n") !== false) break;
}
socket_close($sock);
die("Server said: $str");

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