qt - QSslSocket waitForReadyRead 似乎没有工作

Question

这是我编写的同步 TCP 客户端中 read() 语句上方的一小段代码。

    std::cout << "available? " << socket->bytesAvailable() << std::endl;
    socket->waitForReadyRead();
    std::cout << "reading..." << std::endl;
    bytesRead = socket->read(message + totalBytesRead, messageSize - totalBytesRead);

下面一行:

socket->bytesAvailable()

返回 4，显然有数据可供读取。我遇到的问题是 waitForReadyRead() 一直阻塞到默认超时 30 秒。 Read() 然后继续读取下一行中的 0 个字节。

那么如果有字节可供读取，为什么 waitForReadyRead() 会阻塞

Answer 1

来自 QIODevice::waitForReadyRead 文档:

Blocks until new data is available for reading and the readyRead() signal has been emitted, or until msecs milliseconds have passed. If msecs is -1, this function will not time out.

Returns true if new data is available for reading; otherwise returns false (if the operation timed out or if an error occurred).

处理网络连接的最佳原因是使用信号/插槽机制(异步原因)