    RESTOR(VIII)                 11/24/73                RESTOR(VIII)

    NAME
         restor - incremental file system restore

    SYNOPSIS
         restor key [ arguments ]

    DESCRIPTION
         Restor  is  used  to read magtapes dumped with the dump com-
         mand.  The key argument specifies what is to be  done.   Key
         is a character from the set trxw.

           t  The  date  that the tape was made and the date that was
              specified in the dump command are printed.  A  list  of
              all of the i-numbers on the tape is also given.

           r  The tape is read and loaded into the file system speci-
              fied in arguments.  This should  not  be  done  lightly
              (see below).

           x  Each  file on the tape is individually extracted into a
              file whose name is the file's i-number.  If  there  are
              arguments,  they  are interpreted as i-numbers and only
              they are extracted.

           c  If the tape overflows, increment the last character  of
              its name and continue on that drive.  (Normally it asks
              you to change tapes.)

           f  Read the dump from the next argument  file  instead  of
              the tape.

           i  All read and checksum errors are reported, but will not
              cause termination.

           w  In conjunction with the x option, before each  file  is
              extracted,  its i-number is typed out.  To extract this
              file, you must respond with y.

         The x option is used to retrieve individual files.   If  the
         i-number of the desired file is not known, it can be discov-
         ered by following the file  system  directory  search  algo-
         rithm.   First retrieve the root directory whose i-number is
         1.  List this file with ls -fi 1.  This will give names  and
         i-numbers  of  sub-directories.   Iterating, any file may be
         retrieved.

         The r option should only be used to restore a complete  dump
         tape  onto  a clear file system or to restore an incremental
         dump tape onto this.  Thus

            /etc/mkfs /dev/rp0 40600
            restor r /dev/rp0

         is a typical sequence to restore a complete  dump.   Another
         restor  can  be done to get an incremental dump in on top of

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    RESTOR(VIII)                 11/24/73                RESTOR(VIII)

         this.

         A dump followed by a mkfs and a restor is used to change the
         size of a file system.

    FILES
         /dev/mt0

    SEE ALSO
         ls(I), dump(VIII), mkfs(VIII), clri(VIII)

    DIAGNOSTICS
         There are various diagnostics involved with reading the tape
         and writing the disk.  There are also diagnostics if the  i-
         list or the free list of the file system is not large enough
         to hold the dump.

         If the dump extends over more than one tape, it may ask  you
         to  change  tapes.  Reply with a new-line when the next tape
         has been mounted.

    BUGS
         There is redundant information on the  tape  that  could  be
         used  in  case  of  tape  reading  problems.  Unfortunately,
         restor's approach is to exit if anything is wrong.

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