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(8) 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:

       #if  UCB_NKB == 1
       #define NTREC	10
       #endif
       #ifndef		UCB_NKB
       #define NTREC	20
       #endif
       #define MLEN	16
       #define MSIZ	4096

       #define TS_TAPE	1
       #define TS_INODE 2
       #define TS_BITS	3
       #define TS_ADDR	4
       #define TS_END	5
       #define TS_CLRI	6
       #define MAGIC	(int)60011
       #define CHECKSUM (int)84446
       struct		spcl
       {
	    int 	c_type;
	    time_t	c_date;
	    time_t	c_ddate;
	    int 	c_volume;
	    daddr_t	c_tapea;
	    ino_t	c_inumber;
	    int 	c_magic;
	    int 	c_checksum;
	    struct	dinodec_dinode;
	    int 	c_count;
	    char	c_addr[BSIZE];
       } spcl;

       struct		idates
       {
	    char	id_name[16];
	    char	id_incno;
	    time_t	id_ddate;
       };

       NTREC  is  the number of BSIZE (sys/param.h) 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 file system is `/dev/id_nam'.
       id_incno The level number of the dump tape; see dump(8).
       id_ddate The date of the incremental dump in system format see types(5).

FILES

       /etc/ddate

SEE ALSO

       filsys(5), types(5), dump(8), dumpdir(8), restor(8)

3rd Berkeley Distribution														   DUMP(5)