src/MysqlProxy.php
public function recv()
    {
        if ($this->isDuplex) {
            $data = $this->client->recv(-1);
            if ($data === '') {
                $this->onClientClose($this->client);
            } elseif (is_string($data)) {
                $this->onClientReceive($this->client, $data);
            }
            return $data;
        } else {
            $client = self::coPop($this->mysqlClient, $this->timeout);
            if ($client === false) {
                //连接关闭或超时
                return false;
            }
            if ($client->isConnected()) {
                $data = $client->recv($this->timeout / 500);
            } else {
                $data = '';
            }
            $this->mysqlClient->push($client);
            if ($data === '') {
                $this->mysqlClient->close();
                $this->onClientClose($client);
            } elseif (is_string($data)) {
                $this->onClientReceive($client, $data);
            }
            return $data;
        }
    }
public function recv()
    {
        if ($this->isDuplex) {
            $data = $this->client->recv(-1);
            if ($data === '') {
                $this->onClientClose($this->client);
            } elseif (is_string($data)) {
                $this->onClientReceive($this->client, $data);
            }
            return $data;
        } else {
            $client = self::coPop($this->mysqlClient, $this->timeout);
            if ($client === false) {
                //连接关闭或超时
                return false;
            }
            if ($client->isConnected()) {
                $data = $client->recv($this->timeout / 500);
            } else {
                $data = '';
            }
            $this->mysqlClient->push($client);
            if ($data === '') {
                $this->mysqlClient->close();
                $this->onClientClose($client);
            } elseif (is_string($data)) {
                $this->onClientReceive($client, $data);
            }
            return $data;
        }
    }
recv.

@return mixed