index.txt
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 de‐ scription 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_IN‐ ODE. 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)