1 MT(1)                            User Commands                           MT(1)
   2 
   3 
   4 
   5 NAME
   6        mt - magnetic tape control
   7 
   8 SYNOPSIS
   9        mt [-f tapename] command... [count]
  10 
  11 
  12 DESCRIPTION
  13        The mt utility sends commands to a magnetic tape drive. If -f tapename
  14        is not specified, the environment variable TAPE is used.  If TAPE does
  15        not exist, mt uses the device /dev/rmt/0n.
  16 
  17 OPTIONS
  18        The following options are supported:
  19 
  20        -f tapename
  21                       Specifies the raw tape device.
  22 
  23 
  24 OPERANDS
  25        The following operands are supported:
  26 
  27        count
  28                   The number of times that the requested operation is to be
  29                   performed. By default, mt performs command once. Multiple
  30                   operations of command can be performed by specifying count.
  31 
  32 
  33        command
  34                   The following available commands that can be sent to a
  35                   magnetic tape drive are supported. Only as many characters
  36                   as are required to uniquely identify a command need be
  37                   specified.
  38 
  39                   asf
  40                             Specifies absolute space to count file number.
  41                             This is equivalent to a rewind followed by a fsf
  42                             count.
  43 
  44 
  45                   bsf
  46                             Back spaces over count EOF marks. The tape is
  47                             positioned on the beginning-of-tape side of the
  48                             EOF mark.
  49 
  50 
  51                   bsr
  52                             Back spaces count records.
  53 
  54 
  55                   bssf
  56                             Back spaces over the requested number of
  57                             sequential file marks. Sequential file marks are
  58                             where the file marks are one right after the other
  59                             with no other blocks of any kind between the file
  60                             marks. The number argument specifies how many
  61                             sequential file marks to which to space. For
  62                             example, bssf 4 searches backwards to the first
  63                             place where there are 4 sequential file marks and
  64                             positions to the BOP side of the 4th file mark.
  65 
  66                             This command is not supported by all drives.
  67 
  68 
  69                   eof
  70                   weof
  71                             Writes count EOF marks at the current position on
  72                             the tape.
  73 
  74 
  75                   fsf
  76                             Forward spaces over count EOF marks. The tape is
  77                             positioned on the first block of the file.
  78 
  79 
  80                   fsr
  81                             Forward spaces count records.
  82 
  83 
  84                   fssf
  85                             Forward spaces the over requested number of
  86                             sequential file marks. Sequential file marks are
  87                             where the file marks are one right after the other
  88                             with no other blocks of any kind between the file
  89                             marks. The number argument specifies how many
  90                             sequential file marks to which to space. For
  91                             example, fssf 4 searches forwards to the first
  92                             place where there are 4 sequential file marks and
  93                             positions after the 4th file mark.
  94 
  95                             This command is not supported by all drives.
  96 
  97 
  98                   load
  99                             Requests drive load and thread current media. Not
 100                             supported by all drives.
 101 
 102 
 103                   lock
 104                             Prevents media removal.
 105 
 106 
 107                   nbsf
 108                             Back spaces count files. The tape is positioned on
 109                             the first block of the file. This is equivalent to
 110                             count+1 bsfs followed by one fsf.
 111 
 112 
 113                   seek
 114                             Positions to requested logical tape position.
 115 
 116 
 117                   tell
 118                             Gets and prints current logical tape position.
 119 
 120 
 121                   unlock
 122                             Allows media removal.
 123 
 124                   If count is specified with any of the following commands,
 125                   the count is ignored and the command is performed only once.
 126 
 127                   config
 128                                   Reads the drives current configuration from
 129                                   the driver and displays it in st.conf
 130                                   format. See st(7D) for definition of fields
 131                                   and there meanings.
 132 
 133 
 134                   eom
 135                                   Spaces to the end of recorded media on the
 136                                   tape. This is useful for appending files
 137                                   onto previously written tapes.
 138 
 139 
 140                   erase
 141                                   Erases the entire tape.
 142 
 143                                   Some tape drives have option settings where
 144                                   only portions of the tape can be erased. Be
 145                                   sure to select the correct setting to erase
 146                                   the whole tape. Erasing a tape can take a
 147                                   long time depending on the device and/or
 148                                   tape. Refer to the device specific manual
 149                                   for time details.
 150 
 151 
 152                   forcereserve
 153                                   Attempts to break a SCSI II reserve issued
 154                                   by another initiator. When this command
 155                                   completes, the drive is not reserved for the
 156                                   current initiator, but is available for use.
 157                                   This command can be only be executed by
 158                                   those with super-user privileges.
 159 
 160 
 161                   offline
 162                   rewoffl
 163                                   Rewinds the tape and, if appropriate, takes
 164                                   the drive unit off-line by unloading the
 165                                   tape.
 166 
 167 
 168                   release
 169                                   Re-establishes the default behavior of
 170                                   releasing at close.
 171 
 172 
 173                   reserve
 174                                   Allows the tape drive to remain reserved
 175                                   after closing the device. The drive must
 176                                   then be explicitly released.
 177 
 178 
 179                   retension
 180                                   Rewinds the cartridge tape completely, then
 181                                   winds it forward to the end of the reel and
 182                                   back to beginning-of-tape to smooth out tape
 183                                   tension.
 184 
 185 
 186                   rewind
 187                                   Rewinds the tape.
 188 
 189 
 190                   status
 191                                   Prints status information about the tape
 192                                   unit.
 193 
 194                                   Status information can include the sense key
 195                                   reported by the drive, the residual and
 196                                   retries for the last operation, the current
 197                                   tape position reported in file number, and
 198                                   the number of blocks from the beginning of
 199                                   that file. It might also report that WORM
 200                                   media is loaded in that drive.
 201 
 202 
 203 
 204 EXIT STATUS
 205        0
 206             All operations were successful.
 207 
 208 
 209        1
 210             Command was unrecognized or mt was unable to open the specified
 211             tape drive.
 212 
 213 
 214        2
 215             An operation failed.
 216 
 217 
 218 FILES
 219        /dev/rmt/*
 220                      magnetic tape interface
 221 
 222 
 223 SEE ALSO
 224        tar(1), tcopy(1), ar.h(3HEAD), attributes(5), mtio(7I), st(7D)
 225 
 226 BUGS
 227        Not all devices support all options. Some options are hardware-
 228        dependent. Refer to the corresponding device manual page.
 229 
 230 
 231        mt is architecture sensitive. Heterogeneous operation (that is, SPARC
 232        to x86 or the reverse) is not supported.
 233 
 234 
 235 
 236                                  June 21, 2007                           MT(1)