mt(1)								   User Commands							     mt(1)

NAME

       mt - magnetic tape control

SYNOPSIS

       mt [-f tapename] command... [count]

DESCRIPTION

       The  mt	utility  sends	commands to a magnetic tape drive. If -f tapename is not specified, the environment variable TAPE is used. If TAPE
       does not exist, mt uses the device /dev/rmt/0n.

OPTIONS

       The following option is supported:

       -f tapename     Specifies the raw tape device.

OPERANDS

       The following operands are supported:

       count	       The number of times that the requested operation is to be performed. By default, mt performs  command once. Multiple opera-
		       tions of  command may be performed by specifying count.

       command	       Available  commands that can be sent to a magnetic tape drive. Only as many characters as are required to uniquely identify
		       a command need be specified.

		       eof	       Writes count EOF marks at the current position on the tape.
		       weof

		       fsf	       Forward spaces over count EOF marks. The tape is positioned on the first block of the file.

		       fsr	       Forward spaces count records.

		       bsf	       Back spaces over count EOF marks. The tape is positioned on the beginning-of-tape side of the  EOF mark.

		       bsr	       Back spaces count records.

		       nbsf	       Back spaces count files. The tape is positioned on the first block of  the  file.  This	is  equivalent	to
				       count+1 bsf's followed by one fsf.

		       asf	       Specifies absolute space to count file number. This is equivalent to a rewind followed by a fsf count.

		       If count is specified with any of the following commands, the count is ignored and the command is performed only once.

		       eom	       Spaces to the end of recorded media on the tape. This is useful for appending files onto previously written
				       tapes.

		       rewind	       Rewinds the tape.

		       offline	       Rewinds the tape and, if appropriate, takes the drive unit  off-line by unloading the tape.
		       rewoffl

		       status	       Prints status information about the tape unit.

		       retension       Rewinds the cartridge tape completely, then winds it forward to the end of the reel and back to	beginning-
				       of-tape to smooth out tape tension.

		       reserve	       Allows  the  tape  drive  to  remain  reserved  after closing the device. The drive must then be explicitly
				       released.

		       release	       Re-establishes the default behavior of releasing at close.

		       forcereserve    Breaks the reservation of the tape drive held by another host and then reserves the tape drive.	This  com-
				       mand can be executed only with super-user privileges.

		       erase	       Erases  the entire tape. Caution: Some tape drives have option settings where only portions of the tape may
				       be erased. Be sure to select the correct setting to erase the whole tape. Erasing a tape may  take  a  long
				       time depending on the device and/or tape. Refer to the device specific manual for time details.

		       config	       Reads  the  drives  current configuration from the driver and displays it in st.conf format. See st(7D) for
				       definition of fields and there meanings.

EXIT STATUS

       0	All operations were successful.

       1	Command was unrecognized or mt was unable to open the specified tape drive.

       2	An operation failed.

FILES

       /dev/rmt/*      magnetic tape interface

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcsu			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       tar(1), tcopy(1), ar.h(3HEAD), environ(4), attributes(5), mtio( 7I), st(7D)

BUGS

       Not all devices support all options. Some options are hardware-dependent. Refer to the corresponding device manual page.

       mt is architecture sensitive. Heterogeneous operation (that is, SPARC to x86 or the reverse) is not supported.

SunOS 5.10							    1 Sep 2004								     mt(1)