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dump(5) [ultrix man page]

dump(5) 							File Formats Manual							   dump(5)

Name
       dumprestor, dumpdates - incremental dump format

Syntax
       #include <sys/types.h>
       #include <sys/inode.h>
       #include <dumprestor.h>

Description
       Tapes used by and 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:
       #define NTREC	   10
       #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	   dinode	  c_dinode;
	    int       c_count;
	    char      c_addr[BSIZE];
       } spcl;

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

       #define	 DUMPOUTFMT	"%-16s %c %s"	    /* for printf */
				     /* name, incno, ctime(date) */
       #define	 DUMPINFMT "%16s %c %[^
]
"  /* inverse for scanf */

       NTREC  is  the  number of 1024-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 (1) bit for each inode that was dumped.
       TS_ADDR	    A subrecord of a file description.	See c_addr described in the next list.
       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 (1024-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.  For further information, see
       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 char-
		    acter was not present on the file system; otherwise the character is nonzero.  If the block was not present on the	file  sys-
		    tem,  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 in the file 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.  For further information, see
       id_ddate The date of the incremental dump in system format.  For further information, see

Files
See Also
       fs(5), types(5), dump(8), restore(8)

																	   dump(5)

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