MTIO(4)
NAME
mtio − tape device files
DESCRIPTION
The files in /dev/r?t* refer to tape I/O devices. These files are created using the /com/edmtdesc (edit magtape descriptor) command.
The block length associated with /dev/rmt* files is 1024 bytes. Cartridge tape (/dev/rct*) files have a block length of 512 bytes. If you need to change the block length (or change or examine any other parameter of a magtape descriptor file) use /com/edmtdesc.
FILES
Tape device filenames are:
/dev/rmt8 magtape, rewind on file close
/dev/rmt12 magtape, no rewind on file close
/dev/rct8 cartridge tape, rewind on file close
/dev/rct12 cartridge tape, no rewind on file close