CYBER 170 KERMIT
Author:
Jim Knutson, University of Texas.
Language: CDC FTN5 (Fortran 77) and COMPASS Assembler
Version: 2.2
September 1984, Jim Knutson, University of Texas.
2.2.1 June 1985, Mark Miller, S. O. Lidie, Lehigh University.
2.2.2 July 1986, S. O. Lidie, Lehigh University.
3.0
October 1984, Joerg Hallbauer, Cal State University.
3.1
December 1984, Paul Wells, University of Washington.
3.2
February 1987, Steve Roseman, Lehigh University.
3.3
March 1987, Steve Roseman, Lehigh University.
CYBER 170 Kermit Capabilities at a Glance:
Local Operation
Remote Operation
Transfers text files
Transfers binary files
Wildcard Send
^X/^Z interruption
Filename collision avoidance
Can time out
8th-bit prefixing
Repeat count prefixing
Alternate block checks
Terminal emulation
Communications settings
Transmit BREAK
Transaction logging
Session logging
Raw transmit
Sliding windows
Long packets
Act as server
Talk to server
Advanced server functions
Advanced commands for servers
Handle Attribute Packets
Command/Init files
Command Macros
No
Yes
Yes
Yes
Yes
Yes (through micro)
Yes
Yes
Yes
Yes
No
No
No
No
Yes
No
No
No
Yes
Yes
No
No
Limited
No
Yes
No
1. Cyber File Systems
The features of the Cyber's file system that are of greatest interest to
Kermit
users are storage class, file structure, file specifications and
character
sets.
Cyber Storage Classes
The NOS operating system uses the concept of local and permanent file
storage.
This means that files that are to be kept around after a job is finished
must
be moved to permanent storage first. Jobs that wish to use a file
from permanent storage must copy or attach it to local storage before using it.
To send a file from the Cyber, you may GET/ATTACH the file before
entering Kermit, or have Kermit access the file itself. If you request that Kermit
send a
file which is not found as a local file, it will attempt to find a
matching
permanent file. You may restrict Kermit to local or permanent files by
prefixing the file name with L: or P:, respectively. After receiving a file
on the
Cyber do not forget to SAVE/REPLACE/DEFINE the file to make it permanent.
The DIRECTORY command and REMOTE DIRECTORY server command allow the
user to
display the names of available local or permanent files.
Cyber File Structure
Many Cyber files use internal structure information. Cyber Kermit
supports two
file types: Z-type (line image, unit record) called TEXT, and any
other arbitrary file whose data is transferred 8 bits at a time (7.5 bytes per
60-bit
word), called BINARY.
Other internal file structures, such as other
Cyber
Record Manager record types, are not supported by Cyber Kermit.
Cyber File Specification
A NOS file name consists of from one to seven alphanumeric characters.
Special
characters are not allowed in the file name. File names beginning with
ZZ or
SCR should be avoided, since these are commonly used scratch file names.
Cyber Kermit allows a group of files to be specified in a single
file
specification by including the special "wildcard" characters, "*" and
"?". A
"*" matches any string of characters, including no characters at all;
a "?"
matches any single character.
Any number of "*" and "?" may
appear in a
wildcard specification. To complement the selection criteria, suffix a
"-" to
the wildcard specification.
Here are some examples:
*BUG
All files ending in BUG.
*DOG*
All file names containing DOG.
F*
All files whose names start with F.
F?X*
posi-
All
files
whose names start with F and contain X in the third
tion, followed by zero or more characters.
FRED-
All files except FRED.
Wildcard notation is most commonly used to instruct Kermit to send, or
display
a directory of, a group of files. Its usage is similar to capabilities
on many
other computer systems.
Cyber Character Sets
Until the recent NOS/VE operating system, the character set used by most
Cyber
systems was a six bit DISPLAY CODE character set. The six bit
character sets
supported by Cyber Kermit are the 63 and 64 character sets.
These
character
sets differ in the use of the COLON and PERCENT SIGN characters.
There are also several ASCII character sets in use on NOS. One set,
called
6/12 or simply ASCII, uses 6-bit DISPLAY CODE characters with certain
characters set aside as flags to indicate lower case or control characters.
Another ASCII character set is the 8/12 or ASCII8 character set. This
stores
ASCII characters as 8 bits in a 12-bit byte. The exception to this is
that an
EOL (End-Of-Line) is indicated by the usual CDC convention of at least
twelve
bits of 0 (0000B) in the low order bits of the word.
NUL
characters are
represented as 4000B to prevent interpretation as an EOL sequence.
Cyber Kermit will normally automatically recognize the character set when
sending a TEXT file, and will do the appropriate conversions.
The first
buffer
full (approx 1000 characters) from the disk file is examined and the
file is
recognized to be 8/12 ASCII if the top 4 bits of each byte are zero; 6/12
ASCII
if the first 2 characters in any CM word are lower case; display code
otherwise. Received TEXT files are normally converted to 6/12 ASCII.
The SET
TEXT-MODE command allows the user to request specific conversion modes
of DISPLAY, 6/12-ASCII, or 8/12-ASCII, or set AUTO conversion as described
above.
2. Program Operation
Cyber Kermit's prompt is "Kermit-170>". It must be run interactively
and has
no parameters. Commands can be typed in like this:
/kermit
Cyber-170/NOS KERMIT Ver 3.2.0
Kermit-170>send dog*
(87/01/16)
[the files are sent]
Kermit-170>status
[performance statistics are printed]
Kermit-170>receive
[files are received]
Kermit-170>exit
/
Cyber Kermit provides an initialization file capability. It will look
for a
file named KERMINI in the user's local files, and then in the permanent
file
catalog.
If found, Kermit will take commands from this file before
requesting
commands from the user.
Cyber Kermit mimics the DEC-20 style command parser in that a question
mark
followed by a carriage return may be placed anywhere on the
command line
(except for the SEND and DIR commands). This will display the options
available at that point. Unfortunately, the entire command will have to be
retyped
afterwards.
Command keywords may be abbreviated to their shortest unique combination.
This
comes in very handy since Cyber Kermit does not support command
completion.
Cyber Kermit may only be run as a remote Kermit. This Kermit is
"smart" and
hence need not be closely watched during a transfer since it will timeout
in a
deadlock situation.
A Cyber filename is restricted to 7 alphanumeric characters. When a file
is being sent to the Cyber, Kermit will take up to 3 characters of the
extension
(part following a period) of the micro's file name, plus as much as
possible
from the first part of the file name. This will lessen the conflicts
when
transferring a group of files with the same name but different
extensions.
If a file under that name already exists, an "error packet" stating so
will be
sent back to the micro and Cyber Kermit will abort the entire transfer.
If you are having trouble transferring files with Kermit, it may be due
to the
parity.
Cyber Kermit has no way of determining the parity of the
connection
and does not affect it in any way. If you are having problems
getting the
first packet to transfer, then this is probably the problem. If
necessary,
enter a ! TRMDEF command from within Kermit to set the Cyber front-end's
parity
to match that of your micro (eg. ! TRMDEF,PA=N for no parity, !
TRMDEF,PA=E
for even.)
3. Cyber Kermit Commands
The following is a list of Cyber Kermit commands and their descriptions.
! command
single
Execute a NOS command and then return to Kermit.
space
must
follow the ! character.
Note that a
Cyber Kermit will supply
a control statement terminator if needed.
DIRECTORY [filename]
Displays the names of the files local to the user's job, or the
names
of files in the user's permanent file catalog; filename may
be a
wildcard filename.
If
parameter,
the
command is specified with no parameters or the L:
all local files are listed.
If the P:
parameter is used,
all
permanent files are listed.
To list a single local file or subset of local files, the
user may
specify a file name or wildcard file name.
To list a single or
set
precede
subof
permanent
files,
the
user
may
the file
name or
wildcard file name by P:
[The above syntax is also applicable to the REMOTE
DIRECTORY
server
command.]
EXIT, QUIT
Exit from Kermit-170.
You may also stop Kermit-170 in the
midst of a
transfer
or
during
server operations by aborting your local
Kermit
with a CTRL-C.
Connect to the Cyber Kermit (don't
forget
to
first
FINISH
if
you
were using the Cyber Kermit in server mode)
and then
EXIT.
HELP [topic]
Give Help. There's a general help text, plus separate help
texts for
each Kermit-170 command. HELP ? lists the available topics.
PUSH
Exit to NOS command level, saving the current Kermit
environment.
The environment will be restored when Kermit is reentered.
RECEIVE
name in
Receive a file or group of files from the other host.
If the
the header packet is not a legal Cyber file name, the first
7
legal
characters will be used.
If
the
file
already
exits
as a local file, Kermit will
abort the
transfer.
If an error occurs during transfer, the local
file
being
received
will be deleted to allow the transfer to be retried.
After
entering the RECEIVE command, you should escape back
to
your
local
Kermit and give the SEND command.
SEND filename or L:filename or P:filename
Send one or more files to the local (micro) Kermit; filename
may be a
wildcard filename.
The name of each file is passed to the
other Kermit in a file header packet, so that the file
can
be
stored
there
with
the same name.
You should escape back to your local
Kermit and
give the RECEIVE command. If you don't do this fast
the
"send-init" packet may arrive prematurely. To prevent this,
enough
use SET
DELAY or hit the RETURN key on your
does
microcomputer
if
it
not
timeout.
If
you use the first form of this command and no local file(s)
match
your request, your permanent file catalog is
searched
for
matching
file(s).
If you prefix the filename with L:, only your local
files
are searched; if P:, only your permanent file
catalog
is
searched.
(Note
that
for
a permanent file transfer, any local file
which has
the same name as a permanent file being sent, is deleted.)
SERVER
Act as a server for another Kermit. Whatever options were
previously
SET will be used. The server may be shut down from the local
Kermit
by using the BYE or FINISH commands. Generally, you should
use the
FINISH command if you were transferring a file to the Cyber
so that
you may then connect and make the file permanent. The BYE or
LOGOUT
command causes the remote Kermit to logout and thus should
be used
when receiving a file from the Cyber and there is no real
reason to
re-connect.
The following server features are currently supported in
Kermit-170:
GET, SEND, FINISH, BYE, REM DIR
SET keyword value
Establish system-dependent parameters. You can examine their
values
with the SHOW command.
Numeric values may be decimal,
octal
(postfixed with a B), or hexadecimal (postfixed by an H).
The following may be SET:
DEBUG option
Show packet traffic explicitly.
Options are:
ALL Set all debug options (PACKETS and STATES).
LOG-FILE filename
Log states and packets to the specified file.
The
default
log-file is named KERMLOG.
OFF Don't
default).
log
debugging
information (this is the
If
debugging was in effect, turn it off and close the log
file.
PACKETS
Log each incoming and outgoing packet (lengthy).
STATES
Log Kermit state transitions and packet numbers
(brief).
DELAY decimal-number
Sets the number
of
seconds
to
wait before sending the
first
packet.
This gives you time to "escape" back and issue a
RECEIVE
command.
prompted
The default is 2 seconds.
DUPLEX keyword
Changes the method of echoing characters when being
for
commands.
The choices are FULL and HALF. FULL means the
Cyber
will echo the characters you type.
HALF means the
local
system
echoes them.
FULL is the default, and is used by most
hosts.
FILE-MODE ftype
Declares the file mode to be used
while
processing
Cyber
disk
files.
Allowable
values
for ftype are TEXT and BINARY.
TEXT
means that the file contains text in either 8/12 ASCII,
6/12
ASCII,
or
Display
Code (See SET TEXT-MODE command). BINARY
means
that file contains binary data, packed 7.5 8-bit bytes per
60-bit
word.
The default is TEXT.
INIT-RETRY decimal-number
Set the maximum number of retries allowed for the initial
connection before giving up. Default is 15.
RECEIVE parameter value
These commands allow you to specify to the other Kermit
what
the
packets
it sends should look like, or to inform this
Kermit what
to expect.
Value may be specified as a decimal number, an
octal
number (B suffix), or a hexadecimal number (H suffix).
Character
values are specified as
the
numeric
equivalent
of
the
ASCII
character.
END-OF-LINE value
The octal value of the ASCII character which will be
used
as
a
line terminator for packets by the other system.
Carriage
return (15B) is the default.
PACKET-LENGTH value
Maximum packet
length
the other system may send, a
decimal
number, between 20 and 1000, 94 by default.
Size used
is the
minimum
of
this parameter and the SEND PACKET-LENGTH
of the
other Kermit.
PAD-CHARACTER value
Character to use for padding.
Default is NUL.
PAD-LENGTH value
Set the number of padding characters to send before a
packet.
Default is no padding.
QUOTE-CHARACTER value
The printable character to use for quoting of control
characters.
Default
is
#
(43B).
There should be no
reason to
change this.
SYNC-CHARACTER value
The control character that marks the beginning of the
packet.
Normally SOH (Control-A, ASCII 1).
reason
to change this.
There should be no
TIME-OUT value
The number of seconds the other
for
packet
is
Kermit
should
wait
a
before
asking
for
number
of
retransmission.
Default
10
seconds.
RETRY decimal-number
Sets the maximum
retries
allowed for a
particular
packet before giving up. Default is 10.
SEND parameter value
These commands allow you to specify how outgoing packets
should
look, in case the other Kermit has non-standard
requirements.
END-OF-LINE value
The octal value of the ASCII character to be used as
a line
terminator for packets, if one is required by the other
system.
Carriage return (15B) by default.
PACKET-LENGTH value
Maximum packet length to send, decimal number, between
20 and
1000,
94
by
default.
Size
used
is the minimum
of this
parameter and the RECEIVE PACKET-LENGTH of the other
Kermit.
PAD-CHARACTER value
Character to use for padding.
Default is NUL.
PAD-LENGTH value
Set the number of padding characters to send before a
packet.
Default is no padding.
QUOTE-CHARACTER value
The printable character to use for quoting of control
characters.
The default is # (43B).
There should be no
reason to
change this.
SYNC-CHARACTER value
The control character that marks the beginning of the
packet.
Normally SOH (Control-A, ASCII 1).
reason
There should be no
to change this.
TIME-OUT value
How many seconds to wait for a packet
before
trying
again.
Default is 10 seconds.
TEXT-MODE ctype
Sets the character set of TEXT files.
Allowable values for
ctype
are:
AUTO,
DISPLAY, 6/12-ASCII, and 8/12 ASCII.
The
default is
AUTO, which tells Cyber Kermit to attempt to auto-recognize
files
on send, and write 6/12 ASCII files on receive.
SHOW
Display current SET parameters, version of Kermit-170, and
other information.
STATUS
Give statistics about the most recent file transfer.
TAKE filename or L:filename or P:filename
Take Kermit commands from a file. Kermit will first look
in the
user's local files; if not found it will then look in the
permanent
file catalog. You may restrict the search by prefixing the
filename
with "P:" or "L:". (See the SEND command above.)
When an
logical
end-of-record is encountered on the TAKE file, Kermit will
revert to
accepting commands from the terminal.
TAKE commands
cannot be
nested; a TAKE command read from a file will begin reading
commands
from the new file, but at it's end will not revert to the first
file.
Index
!
0
Control-C
1
Debugging
DIR
0
DIRECTORY
Duplex
1
1
EXIT
1
0
File Type
Help
1
0, 1
KERMINI
0
Kermit Initialization
0
Parity
0
PUSH
1
QUIT
1
RECEIVE
1
Receive Files
Retry
1
1
SEND
1
SERVER
1
SET
1
SHOW
1
STATUS
1
TAKE
1
Text Mode
Wildcard
1
0
Table of Contents
1. Cyber File Systems
0
2. Program Operation
0
3. Cyber Kermit Commands
0
Index
3