[unix-history] / usr / man / cat5 / tp.0



TP(5)		    UNIX Programmer's Manual		    TP(5)


N\bNA\bAM\bME\bE
     tp - DEC/mag tape formats

D\bDE\bES\bSC\bCR\bRI\bIP\bPT\bTI\bIO\bON\bN
     _\bT_\bp dumps files to and extracts files from DECtape and
     magtape.  The formats of these tapes are the same except
     that magtapes have larger directories.

     Block zero contains a copy of a stand-alone bootstrap pro-
     gram.  See _\br_\be_\bb_\bo_\bo_\bt(8).

     Blocks 1 through 24 for DECtape (1 through 62 for magtape)
     contain a directory of the tape.  There are 192 (resp. 496)
     entries in the directory; 8 entries per block; 64 bytes per
     entry.  Each entry has the following format:

	  struct {
		  char		  pathname[32];
		  unsigned short  mode;
		  char		  uid;
		  char		  gid;
		  char		  unused1;
		  char		  size[3];
		  long		  modtime;
		  unsigned short  tapeaddr;
		  char		  unused2[16];
		  unsigned short  checksum;
	  };

     The path name entry is the path name of the file when put on
     the tape.	If the pathname starts with a zero word, the
     entry is empty.  It is at most 32 bytes long and ends in a
     null byte.  Mode, uid, gid, size and time modified are the
     same as described under i-nodes (see file system _\bf_\bs(5)).
     The tape address is the tape block number of the start of
     the contents of the file.	Every file starts on a block
     boundary.	The file occupies (size+511)/512 blocks of con-
     tinuous tape.  The checksum entry has a value such that the
     sum of the 32 words of the directory entry is zero.

     Blocks above 25 (resp. 63) are available for file storage.

     A fake entry has a size of zero.

S\bSE\bEE\bE A\bAL\bLS\bSO\bO
     fs(5), tp(1)

B\bBU\bUG\bGS\bS
     The _\bp_\ba_\bt_\bh_\bn_\ba_\bm_\be, _\bu_\bi_\bd, _\bg_\bi_\bd, and _\bs_\bi_\bz_\be fields are too small.


Printed 7/9/88		  May 15, 1985				1
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	4	TP(5) UNIX Programmer's Manual TP(5)
	5
	6
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	8	N\bNA\bAM\bME\bE
	9	tp - DEC/mag tape formats
	10
	11	D\bDE\bES\bSC\bCR\bRI\bIP\bPT\bTI\bIO\bON\bN
	12	_\bT_\bp dumps files to and extracts files from DECtape and
	13	magtape. The formats of these tapes are the same except
	14	that magtapes have larger directories.
	15
	16	Block zero contains a copy of a stand-alone bootstrap pro-
	17	gram. See _\br_\be_\bb_\bo_\bo_\bt(8).
	18
	19	Blocks 1 through 24 for DECtape (1 through 62 for magtape)
	20	contain a directory of the tape. There are 192 (resp. 496)
	21	entries in the directory; 8 entries per block; 64 bytes per
	22	entry. Each entry has the following format:
	23
	24	struct {
	25	char pathname[32];
	26	unsigned short mode;
	27	char uid;
	28	char gid;
	29	char unused1;
	30	char size[3];
	31	long modtime;
	32	unsigned short tapeaddr;
	33	char unused2[16];
	34	unsigned short checksum;
	35	};
	36
	37	The path name entry is the path name of the file when put on
	38	the tape. If the pathname starts with a zero word, the
	39	entry is empty. It is at most 32 bytes long and ends in a
	40	null byte. Mode, uid, gid, size and time modified are the
	41	same as described under i-nodes (see file system _\bf_\bs(5)).
	42	The tape address is the tape block number of the start of
	43	the contents of the file. Every file starts on a block
	44	boundary. The file occupies (size+511)/512 blocks of con-
	45	tinuous tape. The checksum entry has a value such that the
	46	sum of the 32 words of the directory entry is zero.
	47
	48	Blocks above 25 (resp. 63) are available for file storage.
	49
	50	A fake entry has a size of zero.
	51
	52	S\bSE\bEE\bE A\bAL\bLS\bSO\bO
	53	fs(5), tp(1)
	54
	55	B\bBU\bUG\bGS\bS
	56	The _\bp_\ba_\bt_\bh_\bn_\ba_\bm_\be, _\bu_\bi_\bd, _\bg_\bi_\bd, and _\bs_\bi_\bz_\be fields are too small.
	57
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	63	Printed 7/9/88 May 15, 1985 1
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