hpio(1) CLIX hpio(1)
NAME
hpio - Archives files to Hewlett-Packard 2645A terminal tape drives
SYNOPSIS
hpio -o [rc] file ...
hpio -i [rta] [-n count]
FLAGS
The following flags are available:
-o This flag, when combined with the hpio command, forms a ``copy
out'' command. It copies the specified files, together with
pathname and status information to a tape drive on your
terminal, which is assumed to be positioned at the beginning of
a tape or immediately after a tape mark. The left tape drive
is used by default. Each file is written to a separate tape
file and terminated with a tape mark. When hpio finishes, the
tape is positioned following the last tape mark written.
-i This flag combines with the hpio command to form a ``copy in''
command. It extracts files from a tape drive (which is assumed
to be positioned at the beginning of a file that was previously
written by an hpio -o). The default action extracts the next
file from the left tape drive.
r Use the right tape drive.
c Include a checksum at the end of each file. The checksum is
always checked by hpio -i for each file written with this
option by hpio -o.
-n count The number of input files to be extracted is set to count. If
this variable is not given, count defaults to 1. An
arbitrarily large count may be specified to extract all files
from the tape. The hpio command will stop at the end of data
mark on the tape.
t Display a table of contents only. No files are created.
Displayed information gives the file size in bytes, the
filename, the file access modes, and whether or not a checksum
is included for the file.
a Ask before creating a file. The hpio -i command normally
displays the file size and name, creates and reads in the file,
and displays a status message when the file has been read in.
If a checksum is included with the file, it reports whether the
checksum matched its computed value. With this flag, the file
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hpio(1) CLIX hpio(1)
size and name are displayed followed by a ?. Any response
beginning with y or Y will cause the file to be copied in as
above. Any other response will cause the file to be skipped.
DESCRIPTION
The hpio command is designed to take advantage of the tape drives on
Hewlett-Packard 2645A terminals. Up to 255 CLIX system files can be
archived onto a tape cartridge for off-line storage or for transfer to
another CLIX system. The actual number of files depends on the sizes of
the files. One file of about 115,000 bytes will almost fill a tape
cartridge. Almost 300 1-byte files will fit on a tape, but the terminal
will not be able to retrieve files after the first 255. This manual page
is not intended to be a guide for using tapes on Hewlett-Packard 2645A
terminals, but tries to give enough information to be able to create and
read tape archives and to position a tape for access to a desired file in
an archive.
The hpio command always leaves the tape positioned after the last file
read from or written to the tape. Tapes should always be rewound before
the terminal is turned off. To rewind a tape, press the green function
button, then the <F5> function key. Next select the appropriate tape
drive by pressing either <F5> for the left tape drive or <F6> for the
right. If several files have been archived onto a tape, the tape may be
positioned at the beginning of a specific file by pressing the green
function button, then <F8>. Next, enter the desired file number (1-255)
with no <Return> and press <F5> for the left tape or <F6> for the right.
The desired file number may also be specified by a signed number relative
to the current file number.
EXAMPLES
1. To copy files to the left tape drive on your system, enter the
following:
hpio -o weasel.out worm.out wathel.out
2. If users want to generate a table of contents only, they can use this
command line:
hpio -it
3. To get the first nine files on the tape, use the following:
hpio -in 9
FILES
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hpio(1) CLIX hpio(1)
/dev/tty??
Block messages while accessing a tape
NOTES
Some binary files contain sequences that will confuse the terminal.
An hpio -i that encounters the end of data mark on the tape (for example,
scanning the entire tape with hpio -itn 300), leaves the tape positioned
after the end of data mark. If a subsequent hpio -o is done at this
point, the data will not be retrievable. The tape must be repositioned
manually using the terminal FIND FILES -1 operation (press the green
function button, followed by the <F8> function key. Next, press <F5> for
the left tape or <F6> for the right tape before the hpio -o is started.
If an interrupt is received by hpio while a tape is being written, the
terminal may be left with the keyboard locked. If this happens, the
terminal's RESET TERMINAL key will unlock the keyboard.
CAUTIONS
Tape I/O operations may copy bad data if any other I/O involving the
terminal occurs. Do not attempt any type ahead while hpio is running.
The hpio command turns off write permissions for other users while it is
running, but processes started asynchronously from your terminal can still
interfere. The most common indication of this problem, while a tape is
being written, is the appearance of characters on the display screen that
should have been copied to tape.
The keyboard, including the terminal <Break> key, is locked during tape
write operations; <Break> is only functional between writes.
The hpio command must have complete control of the attributes of the
terminal to communicate with the tape drives. Interaction with commands
such as cu may interfere and prevent successful operation.
DIAGNOSTICS
BREAK An interrupt signal terminated processing.
Can't create `file'.
File system access permissions did not allow file to be created.
Can't get tty options on stdout.
The hpio command was unable to get the input-output control
settings associated with the terminal.
Can't open `file'.
The file could not be accessed to copy it to tape.
End of Tape.
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hpio(1) CLIX hpio(1)
No tape record was available when a read from a tape was requested.
An end of data mark is the usual reason for this, but it may also
occur if the wrong tape drive is being accessed and no tape is
present.
`file' not a regular file.
The file is a directory or other special file. Only regular
file(s) will be copied to tape.
Readcnt = rc, termcnt = tc.
The hpio command expected to read rc bytes from the next block on
the tape, but the block contained tc bytes. This is caused by
having the tape improperly positioned or by a tape block being
mangled by interference from other terminal I/O.
Skip to next file failed.
An attempt to skip over a tape mark failed.
Tape mark write failed.
An attempt to write a tape mark at the end of a file failed.
Write failed.
A tape write failed. This is most frequently caused by specifying
the wrong tape drive, running off the end of the tape, or trying to
write on a tape that is write protected.
EXIT VALUES
Exit codes are 0 for normal termination and 1 for all errors.
RELATED INFORMATION
Commands: cu(1)
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