Command ReferenceA-167
The protocol is comprised of the following commands, which are sent as indi-
cated - no spaces are supplied between the command and its arguments, or
between its arguments, and \n indicates that a newline should be supplied:
Odevice\nmode\n
Open the specified device using the indicated mode. device is a tape name
of the form described in tape and mode is an ASCII representation of a deci-
mal number specifying how the tape is to be opened:
0read-only
1write-only
2read-write
If a device had already been opened, it is closed before a new open is performed.
Cdevice\n
Close the currently open device. The device specified is ignored.
Lwhence\noffset\n
Performs no operation, and returns the value of offset; UNIX-style lseek
operations are ignored on Dell filer tape devices, just as they are on tape
devices on many UNIX systems.
Wcount\n
Write data onto the open device. If count exceeds the maximum data buffer
size (64 kilobytes), it is truncated to that size. /etc/rmt then reads count
bytes from the connection, aborting if a premature end-of-file is encoun-
tered. The response value is the number of bytes written if the write
succeeds, or -1 if the write fails.
Rcount\n
Read count bytes of data from the open device. If count exceeds the maxi-
mum data buffer size (64 kilobytes), it is truncated to that size. /etc/rmt then
attempts to read count bytes from the tape and responds with Acount-
read\n if the read was successful; otherwise an error in the standard format
is returned. If the read was successful, the data read is then sent.
Ioperation\ncount\n
Perform a special tape operation on the open device using the specified
parameters. The parameters are interpreted as ASCII representations of the
decimal values. operation is one of:
0write end-of-file marker
1forward space count files
2backward space count files
3forward space count tape blocks
4backward space count tape blocks
rmt