The -L option during restores is used as a comparison. BRU will read the label string given and attempt to match it to the label of the tape or archive device. If the label does not match on the first tape, BRU will abort the operation. If the label does not match on subsequent tapes, a warning is issued, but the extraction or restore will continue.
There are two ways of providing this label to BRU. The first is to simply specify the label from the command line as shown below:
bru -xv -L “Test Label” /usr/bin
The second method of providing the label string to BRU, is to create a file and tell BRU to read that file. In this fashion BRU will read in the first 63 characters of the file as the label for the tape as shown below:
bru -x -L “/tmp/label name” /usr/bin
The label information appears in the archive header, which can be viewed (or fed to an archive manager program) using BRU’s -g option. NOTE: That the label string and file name are enclosed in a pair of double quotes. This assures that any shell program you might be running (sh, csh, ksh, tsh) will treat the label as a single parameter. If the label is not enclosed in double quotes, BRU will see the individual components of the label string as separate parameters. In the second case, /tmp/label would become the label, and each of the words in the rest of the label – in this case ‘name’ – would be treated as a file name.