unixdev.net


Switch to SpeakEasy.net DSL

The Modular Manual Browser

Home Page
Manual: (v7man)
Page:
Section:
Apropos / Subsearch:
optional field

DUMP(5)                       File Formats Manual                      DUMP(5)



NAME
       dump, ddate - incremental dump format

SYNOPSIS
       #include <&lt;sys/types.h>&gt;
       #include <&lt;sys/ino.h>&gt;
       # include <&lt;dumprestor.h>&gt;

DESCRIPTION
       Tapes used by dump and restor(1) contain:

              a header record
              two groups of bit map records
              a group of records describing directories
              a group of records describing files

       The  format  of  the  header  record  and  of  the first record of each
       description as given in the include file &lt;dumprestor.h&gt; is:

       NTREC is the number of 512 byte records in a physical tape block.  MLEN
       is the number of bits in a bit map word.  MSIZ is the number of bit map
       words.

       The TS_ entries are used in the c_type field to indicate what  sort  of
       header this is.  The types and their meanings are as follows:

       TS_TAPE Tape volume label
       TS_INODE
               A  file  or directory follows.  The c_dinode field is a copy of
               the disk inode and contains bits telling what sort of file this
               is.
       TS_BITS A  bit  map follows.  This bit map has a one bit for each inode
               that was dumped.
       TS_ADDR A subrecord of a file description.  See c_addr below.
       TS_END  End of tape record.
       TS_CLRI A bit map follows.  This bit map contains a zero  bit  for  all
               inodes that were empty on the file system when dumped.
       MAGIC   All header records have this number in c_magic.
       CHECKSUM
               Header records checksum to this value.

       The fields of the header structure are as follows:

       c_type   The type of the header.
       c_date   The date the dump was taken.
       c_ddate  The date the file system was dumped from.
       c_volume The current volume number of the dump.
       c_tapea  The current number of this (512-byte) record.
       c_inumber
                The  number  of  the  inode  being  dumped  if this is of type
                TS_INODE.
       c_magic  This contains the value MAGIC above, truncated as needed.
       c_checksum
                This contains whatever value is needed to make the record  sum
                to CHECKSUM.
       c_dinode This  is a copy of the inode as it appears on the file system;
                see filsys(5).
       c_count  The count of characters in c_addr.
       c_addr   An array of characters describing the  blocks  of  the  dumped
                file.   A  character is zero if the block associated with that
                character was not present on the file  system,  otherwise  the
                character  is  non-zero.   If the block was not present on the
                file system, no block was dumped; the block will  be  restored
                as  a  hole  in the file.  If there is not sufficient space in
                this record to describe all of the blocks in a  file,  TS_ADDR
                records  will  be scattered through the file, each one picking
                up where the last left off.

       Each volume except the last ends with a tapemark (read  as  an  end  of
       file).   The  last  volume ends with a TS_END record and then the tape-
       mark.

       The structure idates describes an entry of the  file  /etc/ddate  where
       dump history is kept.  The fields of the structure are:

       id_name  The dumped filesystem is `/dev/id_nam'.
       id_incno The level number of the dump tape; see dump(1).
       id_ddate The  date  of  the  incremental  dump  in  system  format  see
                types(5).

FILES
       /etc/ddate

SEE ALSO
       dump(1), dumpdir(1), restor(1), filsys(5), types(5)



                                                                       DUMP(5)