qemu: read monitor socket buffer after every write

Author: olljanat

drivers/qemu/driver.go

@@ -824,15 +824,19 @@ func sendQemuShutdown(logger hclog.Logger, monitorPath string, userPid int) erro
 		return err
 	}
 	defer monitorSocket.Close()
+	buf := make([]byte, 512)
+	monitorSocket.Read(buf)
 	logger.Debug("sending qmp_capabilities command to qemu monitor socket", "monitor_path", monitorPath, "pid", userPid)
 	_, err = monitorSocket.Write([]byte(qemuQmpCapabilitiesMsg))
 	if err != nil {
 		logger.Warn("failed to send qmp capabilities message", "qmp capabilities message", qemuGracefulShutdownMsg, "monitorPath", monitorPath, "userPid", userPid, "error", err)
 	}
+	monitorSocket.Read(buf)
 	logger.Debug("sending graceful shutdown command to qemu monitor socket", "monitor_path", monitorPath, "pid", userPid)
 	_, err = monitorSocket.Write([]byte(qemuGracefulShutdownMsg))
 	if err != nil {
 		logger.Warn("failed to send shutdown message", "shutdown message", qemuGracefulShutdownMsg, "monitorPath", monitorPath, "userPid", userPid, "error", err)
 	}
+	monitorSocket.Read(buf)
 	return err
 }