tm(4) [v7 man page]
TM(4) Kernel Interfaces Manual TM(4) NAME
tm - TM-11/TU-10 magtape interface DESCRIPTION
The files mt0, ..., mt7 refer to the DEC TU10/TM11 magtape. When closed it can be rewound or not, see below. If it was open for writing, two end-of-files are written. If the tape is not to be rewound it is positioned with the head between the two tapemarks. If the 0200 bit is on in the minor device number the tape is not rewound when closed. A standard tape consists of a series of 512 byte records terminated by an end-of-file. To the extent possible, the system makes it possi- ble, if inefficient, to treat the tape like any other file. Seeks have their usual meaning and it is possible to read or write a byte at a time. Writing in very small units is inadvisable, however, because it tends to create monstrous record gaps. The mt files discussed above are useful when it is desired to access the tape in a way compatible with ordinary files. When foreign tapes are to be dealt with, and especially when long records are to be read or written, the `raw' interface is appropriate. The associated files are named rmt0, ..., rmt7. Each read or write call reads or writes the next record on the tape. In the write case the record has the same length as the buffer given. During a read, the record size is passed back as the number of bytes read, provided it is no greater than the buffer size; if the record is long, an error is indicated. In raw tape I/O, the buffer must begin on a word boundary and the count must be even. Seeks are ignored. A zero byte count is returned when a tape mark is read, but another read will fetch the first record of the new tape file. FILES
/dev/mt?, /dev/rmt? SEE ALSO
tp(1) BUGS
If any non-data error is encountered, it refuses to do anything more until closed. In raw I/O, there should be a way to perform forward and backward record and file spacing and to write an EOF mark. TM(4)
Check Out this Related Man Page
ANSITAPE(LOCAL) ANSITAPE(LOCAL) NAME
ansitape - ANSI standard tape handler SYNOPSIS
ansitape [key] [keyargs] [files] DESCRIPTION
Ansitape reads and writes magnetic tapes written in ANSI standard format (called ``Files-11'' by DEC). Tapes written by ansitape are labeled with the first 6 characters of the machine name by default. Actions are controlled by the key argument. The key is a string of characters containing at most one function letter. Other arguments to the command are a tape label and file names specifying which files are to be written onto or extracted from the tape. The function portion of the key is specified by one of the following letters: r The named files are written at the end of the tape. The c function implies this. x The named files are extracted from the tape. If no file argument is given, the entire contents of the tape is extracted. Note that if the tape has duplicated file names, only the last file of a given name can be extracted. t The names of the specified files are listed each time they occur on the tape. If no file argument is given, all files on the tape are listed. c Create a new tape; writing begins at the beginning of the tape instead of after the last file. This command implies r. The following characters may be used in addition to the letter which selects the function desired. f This argument allows the selection of a different tape device. The next word in the keyargs list is taken to be the full name of a device to write the tape on. The default is /dev/rmt12. n The n option allows the user to specify as the next argument in the keyargs list, a control file containing the names of files to put on the tape. If the file name is '-', the control file will, instead, be read from standard input. The control file contains one line for each file to be placed on the tape. Each line has two names, the name of the file on the local machine, and the name it is to have when placed on the tape. This allows for more convenient flattening of hierarchies when placing them on tape. If the second name is omitted, the UNIX file name will be used on the tape also. This argument can only be used with the r and c functions. l The l option allows the user to specify the label to be placed on the tape. The next argument in the keyargs list is taken as the tape label, which will be space padded or truncated to six characters. This option is meaningless unless c is also specified. v Normally ansitape works relatively silently. The v (verbose) option causes it to type information about each file as it processes it. b The b option allows the user to select the blocksize to be used for the tape. By default, ansitape uses the maximum block size permitted by the ANSI standard, 2048. Some systems will permit a much large block size, and if large files are being put on the tape it may be advantageous to do so. Ansitape will take the next argument of the keyargs list as the blocksize for the tape. Values below 18 or above 32k will be limited to that range. The standard scale factors b=512 and k=1024 are accepted. Ansitape will not copy directories, character or block special files, symbolic links, sockets, or binary executables. Attempts to put these on tape will result in warnings, and they will be skipped completely. FILES
/dev/rmt12 DIAGNOSTICS
A warning message will be generated when a record exceeds the maximum record length and the affected file will be truncated. BUGS
Ansitape quietly truncates names longer than 17 characters. ANSI 'f' format files can be read but not written. Multivolume tapes can not be handled. 4/10/85 UCB Local ANSITAPE(LOCAL)