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tskipf(3f) [bsd man page]

TOPEN(3F)																 TOPEN(3F)

NAME
topen, tclose, tread, twrite, trewin, tskipf, tstate - f77 tape I/O SYNOPSIS
integer function topen (tlu, devnam, label) integer tlu character*(*) devnam logical label integer function tclose (tlu) integer tlu integer function tread (tlu, buffer) integer tlu character*(*) buffer integer function twrite (tlu, buffer) integer tlu character*(*) buffer integer function trewin (tlu) integer tlu integer function tskipf (tlu, nfiles, nrecs) integer tlu, nfiles, nrecs integer function tstate (tlu, fileno, recno, errf, eoff, eotf, tcsr) integer tlu, fileno, recno, tcsr logical errf, eoff, eotf DESCRIPTION
These functions provide a simple interface between f77 and magnetic tape devices. A ``tape logical unit'', tlu, is ``topen''ed in much the same way as a normal f77 logical unit is ``open''ed. All other operations are performed via the tlu. The tlu has no relationship at all to any normal f77 logical unit. Topen associates a device name with a tlu. Tlu must be in the range 0 to 3. The logical argument label should indicate whether the tape includes a tape label. This is used by trewin below. Topen does not move the tape. The normal returned value is 0. If the value of the function is negative, an error has occured. See perror(3F) for details. Tclose closes the tape device channel and removes its association with tlu. The normal returned value is 0. A negative value indicates an error. Tread reads the next physical record from tape to buffer. Buffer must be of type character. The size of buffer should be large enough to hold the largest physical record to be read. The actual number of bytes read will be returned as the value of the function. If the value is 0, the end-of-file has been detected. A negative value indicates an error. Twrite writes a physical record to tape from buffer. The physical record length will be the size of buffer. Buffer must be of type char- acter. The number of bytes written will be returned. A value of 0 or negative indicates an error. Trewin rewinds the tape associated with tlu to the beginning of the first data file. If the tape is a labelled tape (see topen above) then the label is skipped over after rewinding. The normal returned value is 0. A negative value indicates an error. Tskipf allows the user to skip over files and/or records. First, nfiles end-of-file marks are skipped. If the current file is at EOF, this counts as 1 file to skip. (Note: This is the way to reset the EOF status for a tlu.) Next, nrecs physical records are skipped over. The normal returned value is 0. A negative value indicates an error. Finally, tstate allows the user to determine the logical state of the tape I/O channel and to see the tape drive control status register. The values of fileno and recno will be returned and indicate the current file and record number. The logical values errf, eoff, and eotf indicate an error has occurred, the current file is at EOF, or the tape has reached logical end-of-tape. End-of-tape (EOT) is indicated by an empty file, often referred to as a double EOF mark. It is not allowed to read past EOT although it is allowed to write. The value of tcsr will reflect the tape drive control status register. See ht(4) for details. FILES
/usr/lib/libU77.a SEE ALSO
ht(4), perror(3F), rewind(1) 4.2 Berkeley Distribution May 15, 1985 TOPEN(3F)

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AMTAPE(8)						      System Manager's Manual							 AMTAPE(8)

NAME
amtape - user interface to Amanda tape changer controls SYNOPSIS
amtape config command [ command options ] DESCRIPTION
Amtape performs tape changer control operations. It uses the underlying tape changer script defined by the tpchanger option for a particu- lar Amanda configuration as specified by the config argument. Tape changers maintain a notion of the current and next slot for each configuration. These may or may not correspond to an actual physical state of the device, but do tend to minimize searching through the tape storage slots. If the desired tape is in the current slot, it is likely the next tape needed is in the next slot rather than at some random position in the storage slots. See the amanda(8) man page for more details about Amanda. COMMANDS
reset Reset the tape changer to a known state. The current slot is set to the first slot. Other device-specific side effects may occur. Some gravity stackers need to be reset to the top position by hand. This command notifies Amanda the stacker is back in that posi- tion. eject If a tape is loaded in the drive, it is ejected and returned to the slot from which it was loaded. clean If a cleaning tape is defined for the changer, it is used to clean the drive. show Show the contents of all slots. This can be slow. label label Search for and load the Amanda tape with label label. taper Perform the taper scan algorithm. Load the next tape in the configuration's tape sequence, or a fresh tape with a suitable label. device Display the name of the current tape device on stdout. current Display the current slot. update Update the changer label database, if it has one, to match the tapes now available. slot slot Eject any tape in the drive and put it away, then load the tape from slot slot and reset current. slot current Eject any tape in the drive and put it away, then load the tape from the current slot. slot prev Eject any tape in the drive and put it away, then load the tape from the previous slot and reset current. slot next Eject any tape in the drive and put it away, then load the tape from the next slot and reset current. slot first Eject any tape in the drive and put it away, then load the tape from the first slot and reset current. slot last Eject any tape in the drive and put it away, then load the tape from the last slot and reset current. slot advance Eject any tape in the drive and put it away. Advance current to the next tape, but do not load it. This is useful with non-gravity stackers to unload the last tape used and set up Amanda for the next run. If you just use eject, the current tape will be mounted again in the next run, where it will be rejected as being still in use, ejected and the next tape requested. Using slot next followed by eject does an unnecessary mount. Note: most changers optimize the slot commands to not eject the loaded tape if it is the one being requested. AUTHOR
James da Silva <jds@cs.umd.edu> University of Maryland, College Park SEE ALSO
amanda(8) AMTAPE(8)

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