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I have some backup tapes which existed on an AUSPEX file server. The backups were written to tape with the SunOs version of the CPIO command. Now that I need to restore them, (of course there are no more auspex servers in existance), the backups won't restore because the headers are not standard. I have dumped the tape images to disk. PAX, CPIO, and TAR cannot read the images. I've tried all of the CPIO format options.

The errors I get are "name too long", "byte swapped in header", or just junk output.

I can open up the images and read the contents of the files, but cannot restore the images.

I have found that SunOs had a special header in CPIO V2.5 images. I have found the source for cpio, now I need definition of the SunOs header inside CPIO?

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I don't haven an old-style cpio archive around anymore, I think, but considering the evolution of the program, I'm confident that Jörg Schillings star should be able to extract files from that format. It's even pretty good at finding out about the format of the file itself, so chances are, you don't have to try around with the multitude of options (byte-swapped, halfword-swapped, crc checksummed header, etc).

Header types:
    v7tar   Old UNIX V7 tar format
    tar     Old BSD tar format
    star    Old star format from 1985
    gnutar  GNU tar format 1989 (violates POSIX)
    ustar   Standard POSIX.1-1988 tar format
    xstar   Extended standard tar (star 1994)
    xustar  'xstar' format without tar signature
    exustar 'xustar' format - always x-header
    pax     Extended POSIX.1-2001 standard tar
    suntar  Sun's extended pre-POSIX.1-2001
    bin     cpio UNIX V7 binary format
    cpio    cpio POSIX.1-1988 format
    odc     cpio POSIX.1-1988 with SYSv compat
    asc     SYSvr4 cpio ascii expanded device #
    crc     'asc' format + CRC

When called as scpio, scpio -help will give more detailled help on the cpio specific options.

It can be downloaded via ftp from berlios

(link verified: 2013-09-06)

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