DUMP(5) 							File Formats Manual							   DUMP(5)

NAME

       dump, ddate - incremental dump format

SYNOPSIS

       #include <sys/types.h>
       #include <sys/ino.h>
       # include <dumprestor.h>

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 <dumprestor.h> 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)