vary offline

1. To change the status of a device from online to offline. When a device is off line, no data set may be opened on that device.; 将设备的联机状态改为脱机状态。当设备脱机时，在此设备上不能打开任何数据集。 2. To place a device in a state where it is not available for use by the system; however, it is still available for executing I/O. | 把设备置于系统不能使用的状态，然而，对于执行输入输出，它仍然是可用的。