# 3.4 Tar Request a Second Tape On an SGI

## Problem

When attempting to tar off MATLAB on a 4/8mm tape drive on a SGI, it asks for a 2nd tape. Just pressing the Enter key (there is no second tape) causes an error.

    # tar -xvf  device

Change tape and press the Enter key:

    tar: tape read error:
    #

## Solution

You must use the device that ends in 'v' for variable blocksize.

For example, the standard device we recommend using is:

    /dev/rmt/tps0d1ns

then the correct device is the same device with a 'v' appended to the end, i.e.

    /dev/rmt/tps0d0nsv

NOTE: The convention on naming the device is

    /dev/{r}mt/tps<controller-#>d<ID-#>{nr}{ns}{v}{.density}

If this device does not exist it must be 'made'.

To make the device, first become root and then:

    # cd /dev
    # MAKEDEV device

where the device depends on the situation. The most common is 'tps'. For example, to make all the tps devices, then

    # cd /dev
    # MAKEDEV tps

(c) Copyright 1994 by The MathWorks, Inc.