A lot of people were having problems with appending archives (and
some with creating archives) because of the fact that taper updated
the directory at the beginning of the tape. Some tape devices just
didn't like that - they were writing EOF marks all over the place,
getting into infinite loops and some just downright refusing to do it.
This was especially true for SCSI users (mainly because I couldn't
debug them since I have no SCSI access).

Therefore, I have come up with another way of maintaing information
about an archive so that one can quickly ascertain what is on a tape. 
This is through the use of archive information files. Below is an 
extract from the README file pertaining to the information files.

Using this method, data is only appended to an archive - there is
no updating of information on a tape, so hopefully the obstinate 
tape drives shouldn't object. 


I solved this by maintaining an archive information file on the hard disk.
This file contains all the information about files stored on the archive.
When files are added to the archive, the archive information file is
updated. This archive information file can be reconstructed from the
archive should the file get deleted/corrupted/lost - it just takes 
time. Should you wish to restore an archive on a different machine than
one to where the backup was made, you have two options: 1) make a copy 
of the information file on a floppy and take this floppy with you as
well as the tape, 2) reconstruct the archive information file on the
restoring machine. Since reconstructing the archive information file
can take a while, method 1 is recommended. Archive information files are
not long - they occupy 56 bytes + length of the filename for each file - 
thus 10,000 files of average filename length of 20 chars is less than
800K (even less with compression) - easily fits on most floppies. 


The downside is that the new taper archives aren't compatible with old
ones. I have not made version 4 able to read old style backups since
I didn't really think there was much need. If you want to keep the 
old taper versions to read these archives, fine; I think a more
sensible way would be to recreate all you archives with version 4 style
archives then dispose of your old taper versions.

