dump/restore

[Doug Gwyn]

In article <262 at mpx2.UUCP> erik at mpx2.UUCP (Erik Murrey) writes:
>Sys-V tar doesn't copy directory permissions (or even directory
>entries!) to the tape.  This means that empty directories don't
>get backed up and permissions get guessed during a restore.  This
>stinks.  (I know BSD's tar does this correctly)

UNIX System V's "tar" was provided simply for compatibility reasons.
It is essentially the 7th Edition version and has numerous problems.
Like 7th Edition, directories are not in the archive; whenever a
directory is needed but not present during extraction, it is created
using the current default umask.  This feature is necessary whether
or not directories are recorded in the archive.

One of Berkeley's infamous "better ideas" was to stash directory
entrites in the archive before their contents.  Unfortunately, if
a directory did not have write permission, when restoring a batch
of files from the archive creation of the directory will preclude
successful extraction of the subsequent files within it.

>I like cpio becuase it dumps everything to tape.  Even directories
>and special files like named pipes, etc.  I does not, however, allow
>you to split the backup across several tapes (or disks).  This
>is a big loss for people without tape drives (me).

UNIX has never had a good, standard way to deal with multi-volume
files.