dump(5)

NAME
     dump, dumpdates - incremental dump format

SYNOPSIS
     #include <sys/types.h>
     #include <protocols/dumprestore.h>

DESCRIPTION
     Tapes used by dump and restore(1M) 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 <protocols/dumprestore.h> is:

          #define TP_BSIZE                1024
          #define NTREC          10
          #define LBLSIZE        16
          #define NAMELEN        64

          #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 bsd_dinode        c_dinode;
                  int             c_count;
                  char            c_addr[TP_BSIZE/2];
                  char            c_label[LBLSIZE];
                  long            c_level;
                  char            c_filesys[NAMELEN];
                  char            c_dev[NAMELEN];
                  long            c_flags;
          } spcl;

          struct idates {
                  char            id_name[255];
                  char            id_incno;
                  time_t          id_ddate;
          };

          #define DUMPOUTFMT "%-16s %c %s"
          #define DUMPINFMT  "%[^ ] %c %[^\n]\n"


     TP_BSIZE is the size of file blocks on the dump tapes.  NTREC is the
     default number of 1024 byte records in a physical tape block (blocking
     factor).

     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 indicating the type of
                  the file.
     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 filesystem 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 filesystem 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 filesystem.
                  Extent File System (see fs(4)) disk inodes differ from the
                  Berkeley Fast File System inode format.  Dump converts EFS
                  disk inodes to Berkeley's format, before dumping them on
                  tape.
     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 filesystem, otherwise the
                  character is non-zero.  If the block was not present on the
                  filesystem, 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.
     c_label      Dump label.
     c_level      Level of this dump.  See dump(1M).
     c_filesys    Name of the dumped filesystem.
     c_dev        Name of the dump device.
     c_host       Name of the dumped host.
     c_flags      Additional information.

     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 tapemark.

     The structure idates describes an entry in the file /etc/dumpdates 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(1M).
     id_ddate The date of the incremental dump in system format see types(5).

FILES
     /etc/dumpdates

SEE ALSO
     dump(1M), restore(1M), fs(4), types(5)