The hyphen (-) is a special filename. When it is specified on the BRU command line in place of the files option, it tells BRU to read the standard input stream (stdin) for a list of files to process rather than collecting them from the command line. The rules governing the use of the hyphen as a special filename are the same for both reading and writing archives. This usage takes the form:
bru -x [options] -
This option is typically used in conjunction with a UNIX pipe or with the standard input stream redirected to a file containing a list of filenames. The commands
cat /tmp/filelist | bru -x -
bru -x -
are equivalent and extract the specific list of files you have named. NOTE: filelist must contain all the files, that you wish to restore (not just the directory names). filelist must also be in the same order. You may wish to list the files with ‘bru -tv >filelist’ then edit filelist for the files you want to restore. NOTE: BRU will read your list of files BUT WILL NOT DO WILDCARD EXPANSION of that list of files. BRU expects the list of files to be completely expanded when it receives the list. Therefore WILDCARDS CAN’T BE USED in your list of files for restoring data. NOTE: If you use a hyphen (-) in place of a list of files on the BRU command line, you are not allowed to use the “-f -” option to read an archive from the standard input on the same command line. These two usages conflict. The following command is illegal:
bru -x -f - -
It is not possible for BRU to read both the archive and the list of files from the standard input.