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topen(3f) [bsd man page]

TOPEN(3F)																 TOPEN(3F)

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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BTAPE(8)					     Network backup, recovery and verification						  BTAPE(8)

btape - Bacula's Tape interface test program SYNOPSIS
btape [options] device-name DESCRIPTION
This manual page documents briefly the btape command. OPTIONS
A summary of options is included below. -? Show summary of options and commands. -b bootstrap Specify a bootstrap file. -c config Specify configuration file. -d nn Set debug level to nn. -p Proceed inspite of I/O errors. -t Open the default tape device. -s No signals (for debugging). -v Set verbose mode. COMMANDS
autochanger test autochanger bsf backspace file bsr backspace record cap list device capabilities clear clear tape errors eod go to end of Bacula data for append eom go to the physical end of medium fill fill tape, write onto second volume unfill read filled tape fsf forward space a file fsr forward space a record help print this reference label write a Bacula label to the tape load load a tape quit quit btape rawfill use write() to fill tape readlabel read and print the Bacula tape label rectest test record handling functions rewind rewind the tape scan read() tape block by block to EOT and report scanblocks Bacula read block by block to EOT and report status print tape status test General test Bacula tape functions weof write an EOF on the tape wr write a single Bacula block rr read a single record rb read a single bacula block qfill quick fill command SEE ALSO
bscan(1), bextract(1). AUTHOR
This manual page was written by Jose Luis Tallon <>. Kern Sibbald 26 November 2009 BTAPE(8)

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