NAME

tp − magnetic tape format

DESCRIPTION

The command tp(1) dumps files to and extracts files from magtape.

Block zero contains a copy of a stand-alone bootstrap program; see tapeboot(8).

Blocks 1 through 62 contain a directory of the tape.  There are 496 entries in the directory; 8 entries per block; 64 bytes per entry.  Each entry has the following format:

structtpent{
charpathnam[32];
shortmode;
charuid;
charuid;
chargid;
charspare;
charsize0;
shortsize2;
longtime;
shorttapea;/∗ tape address ∗/
shortunused[8];
shortcksum;/∗ check sum ∗/
}

The pathnam entry is the path name of the file when put on the tape.  If the path name 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, the sizes and time modified are the same as described under i-nodes (fs(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 continuous tape. The checksum entry has a value such that the sum of the 32 words of the directory entry is zero.

Blocks 63 on are available for file storage. 

A fake entry has a size of zero.  See tp(1).

SEE ALSO

cpio(1), tp(1), fs(5), tapeboot(8). 

May 16, 1980