1 .TH mt-dds 1 2.4 \" -*- nroff -*-
5 mt-dds \- tool to control a dds device.
10 .BR comp-on | comp-off | comp-query | comp-log
24 controls the compression mode of dds tape devices (DAT).
27 may also report the current tape position in
28 absolute records (relative to begin of tape) in a format
29 that may be used later by
31 to access tar archives that are not the first file on tape.
35 which may be overridden with the environment variable
37 which in turn may be overridden with the
39 option. The device must be a character special file.
43 .SS DDS tape device control options
47 Enable the hardware compression mode if supported by the device.
50 Disable the compression mode, switch to normal mode.
53 Print to stderr if compression mode currently is disabled
56 means compression is disabled, a
58 means compression in enabled.
61 Print to stdout four lines of information about transferred kilobytes
62 before and after hardware compression from and to the device
65 .SS dds2tar service functions
69 Print three lines with the
70 .BR "current tape position" ", a"
72 value (20 by default, may be overridden with
76 value (blocksize*512) to
78 If this output is redirected to a location file
80 this file may be used by
82 to access archives on tape.
85 If the current tape position is the beginning of an archive and the archive
88 writes the label to stdout
89 and moves the tape back to the
90 current position (or back over the filemark).
93 If the current tape position is the beginning of an archive and the archive
96 writes the timestamp in octal format to stdout
97 and moves the tape back to the
98 current position (or back over the filemark).
99 If you are using only one computer, the timestamp can be used as a unique
103 Specify the block size
105 value that is used as a default for the written value with the
108 Also the internal buffer size is specified with this option
109 which is used to read one block in order to get the block size
110 of the current tape block. So specify the block size of the archive
117 Device of the tape archive (default is /dev/tape).
118 Must be a character special file connected to a dds tape device.
121 Print the version number of
123 to stderr and exit immediately.
126 print some screens of online help with examples through a pager
127 and exit immediately.
132 checking the compression mode of the default tape device
138 Write the location information as
140 command line options to stdout.
149 The environment variable
151 overrides the default tape device /dev/tape.
154 The environment variable
156 overrides the builtin pager command ("/bin/more") to display the output
163 dds2tar(1), dds2index(1), mt(1), tar(1)
167 This program was created to use it in conjunction with dds2tar.
171 J"org Weule (weule@cs.uni-duesseldorf.de), Phone +49 211 751409.
172 This software is available at
173 ftp.uni-duesseldorf.de:/pub/unix/apollo