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INTRO
This website contains an archive of files for the Acorn Electron, BBC Micro, Acorn Archimedes, Commodore 16 and Commodore 64 computers, which Dominic Ford has rescued from his private collection of floppy disks and cassettes.
Some of these files were originally commercial releases in the 1980s and 1990s, but they are now widely available online. I assume that copyright over them is no longer being asserted. If you own the copyright and would like files to be removed, please contact me.
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| Filename: | INTRO |
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| File size: | 47DF bytes |
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| Exec address: | 0000 |
File contents
A BRIEF OVERVIEW OF KERMIT
==========================
This guide provides a brief description of the Kermit file transfer system:
it explains what Kermit is, what it does, and how it does it. The document
has been adapted from a user manual written by Dave Morriss and Joe
Angelosanto of Heriot-Watt University, Edinburgh, Scotland.
1. INTRODUCTION
KERMIT is the name of a file transfer protocol developed at Columbia
University Center for Computing Activities (CUCCA) in New York. The object
of such a protocol is to transfer files between two computers with little
regard to the type of machines engaging in the transfer. KERMIT was
designed to allow the transfer of files between mainframe computers and the
numerous microcomputers that are to be found today in Universities and in
the commercial world. The link between the two machines need only be a
standard asynchronous communications line, of the kind that is used to
attach a terminal to a central computer.
CUCCA have published full information about KERMIT (reference 1), but retain
the copyright. Anyone may implement KERMIT on their own machine, but this
must not be done for commercial purposes. Many people have implemented
versions of KERMIT on many different machines; micro-computer, mini-
computer and mainframe versions have been written.
2. BASIC PRINCIPLES
The components required to transfer a file between two computers, using
KERMIT, are the two computers, each with their own KERMIT program, and a
data communications line joining them both together.
One of the KERMIT programs will run on the local machine under the direct
control of the user. This machine will normally be a microcomputer, and its
KERMIT program will have some form of terminal emulation capability to allow
it to log-on to, and interact with the other machine - the remote computer.
The remote machine, usually a mainframe or mini, will also have a KERMIT
program, to which you can type commands from your micro using its terminal
emulation facility.
The communication link between the two computers can be more or less any
asynchronous (terminal) line. Kermit requires that a CONTROL-A character
can get through the communications equipment, so you may need to adjust the
characteristics of the line to allow this.
An Introduction to Kermit Page 1
A typical KERMIT session would consist of the following steps:
1. The local (micro) KERMIT program is entered in the same way that any
other program is initiated.
2. Any required local configuration is carried out, for example setting the
line speed for the terminal emulator.
3. The terminal emulator is entered, usually with the command CONNECT.
4. Using the emulator, the remote computer is accessed in an identical way
to the use of a normal terminal and an interactive session is begun.
5. The KERMIT program on the remote host computer is entered, and any
necessary configuration commands issued.
6. A file transfer command is issued to the remote KERMIT, depending on
whether you intend to send a file to the remote computer (in this case
you tell the remote KERMIT to RECEIVE), or ask it to send a file to your
local computer (in which case you tell the remote KERMIT to SEND).
7. The terminal emulator on the local KERMIT is then exited by use of a
'local escape' character sequence. This puts the local program back
into the command mode originally entered in step 1.
8. A local file transfer command is issued. This will be SEND or RECEIVE
depending on the direction the transfer is to take. (Naturally, this
command will be the opposite of that issued to the remote machine.)
9. The file transfer will proceed under the control of the two KERMIT
programs until the file has been completely transferred (or a fatal
error has occurred). The local KERMIT will then return to command mode.
10. Using the terminal emulator part of the local KERMIT, the host is
accessed, and the remote KERMIT closed down. The interactive session is
then ended and the local KERMIT terminated; the KERMIT session is now
complete.
If there are several files to be transferred between the local and host
computers steps 6 to 9 above will have to be repeated.
Every time a control command is to be issued to the remote KERMIT, the local
KERMIT must be switched into its terminal emulation mode. To streamline this
process, some remote KERMITs can be run in SERVER mode. A KERMIT server
will accept commands sent by the local KERMIT across the communications link
without the local KERMIT having to switch to terminal emulation mode. This
means that the remote KERMIT can be controlled by commands given to the
local KERMIT.
Not all KERMIT programs offer the same facilities, so the appropriate manual
should always be checked to find out what facilities the KERMITs being used
have. It is no good, for example, putting a remote KERMIT into server mode
if the local KERMIT is not capable of controlling a KERMIT server.
An Introduction to Kermit Page 2
3. AN OUTLINE OF THE PROTOCOL
When information is being transferred between KERMIT programs it is sent in
blocks or packets. A KERMIT packet consists of a sequence of characters
comprising a header, followed by the actual data being communicated, and
terminated with a trailer. The header contains fields which define such
things as the packet length and packet type. The trailer contains a check
sequence which is used by the receiving KERMIT to determine whether the
contents of the packet have arrived intact. Further details of the structure
of a KERMIT packet can be found in Reference 1.
As each packet is received from the sending KERMIT it is checked, and if
correct the receiver sends an acknowledgment (ACK) packet to tell the
sender that the packet has been received and that it was intact. Otherwise a
negative acknowledgment (NAK) packet is sent to indicate a transmission
failure, and this prompts the sender to re-transmit the packet.
The rest of this section describes how the KERMITs go about the actual
transmission of data. This information may be useful for simple debugging. A
more detailed look at the structure of a packet is given in appendix A.
(a) Send-Receive Environment
When a KERMIT file transmission is started, the local and remote KERMITs
exchange initialisation packets. The packet that starts a file transfer is
called a 'send-init' packet. The initialisation packets contain information
about the facilities that each KERMIT supports. The initiator will 'offer'
its own facilities to the other KERMIT which can either agree, or reply with
an initialisation packet containing some restrictions. This negotiation is
used to determine such details as the maximum packet size, the
start-of-packet and end-of-packet marker characters, the type of check
sequence, and so forth.
Once both ends are in agreement about the parameters of the transfer, the
requested file or files can be transferred (multiple file transfers are
catered for by the protocol). Before any data is sent over the link the name
of the file must be established. A file header packet defines the filename
(and optionally some of the other attributes of the file). The filename is
generated by the sender, often using its own filename syntax. This name is
used by the receiver to construct a filename according to its own syntax
rules, though the KERMIT user can usually define the target filename
explicitly. Various strategies may be used by the receiver to handle the
situation where the destination file already exists - data may be appended
to the file, it may over-write the file, or the filename may be altered so
as to avoid the clash.
Once the file header packet has been accepted, the data transfer can begin.
This will proceed one packet at a time, each packet being positively
acknowledged if received intact, or negatively acknowledged if corrupted in
some way. Multiple consecutive failures will usually cause the transfer
to be aborted and an error packet to be transmitted, on the assumption
that the communications medium is unreliable. Packets may be re-transmitted
if acknowledgment is not received within a time limit - a condition known as
a time-out. If everything progresses well, the transfer will end when the
An Introduction to Kermit Page 3
file has been sent. The end of the file is signalled by an end-of-file
packet and, if there are no more files to send, an end-of-transmission
packet is sent. Most KERMIT implementations will allow a series of files to
be sent in a single transaction, and the two types of end packet are needed
for this purpose.
(b) Server Mode
The order and type of packets sent during a KERMIT session is slightly
altered if the remote KERMIT has been put into server mode. For instance,
the local KERMIT might want to send a command to the remote KERMIT, possibly
to change some parameter. This would be done by sending a command packet to
the server. However, the local and remote KERMITs may not have exchanged
information such as packet length, end-of-packet character, check sequence,
etc. (and even if they had, some parameters might change between
transactions). To overcome this potential problem, an init-info packet is
sent to the server prior to most transactions. This type of packet is
exactly like the initialisation packet and is acknowledged in the same way,
but does not cause the server to think that it is about to be sent a file.
When a local KERMIT, which is in control of a remote KERMIT, wishes to
receive a file (usually achieved by issuing the GET command to the local
KERMIT) it sends an init-info packet then, once that has been acknowledged,
an R type packet. The R packet will indicate to the server that it is to
send a file, the name of which will be in the data field of the packet. The
remote KERMIT will respond to this request in one of two ways. If it cannot
find or access the requested file, it will send an error packet which will
contain an appropriate message, otherwise, if all is well, it will send a
send-init packet and the transfer will continue as in (a) above.
For the case when the local KERMIT wants to SEND a file to a server the
transfer proceeds as in (a) above without the need for the init-info packet.
Once a remote KERMIT is in server mode it will only receive packets as
input, so, in order to reconnect to the remote computer to end the session,
it will be necessary to shut down the server first. This is done by typing
the FINISH command to the local KERMIT, which forces a command packet to be
sent to the remote KERMIT telling it to shut down the server.
An Introduction to Kermit Page 4
APPENDIX A: A CLOSER LOOK AT PACKETS
This appendix has been included in order to show what packets actually look
like, and to offer some sort of starting point for debugging. Most KERMITs
offer some sort of debug facility, the output from which will be in a
similar form to the example shown below. Reference 1 will give a more
detailed description of the structure of a packet than will be given here.
The example used here was carried out between a mini and a micro system.
The mini KERMIT was put into server mode and, after escaping back to the
micro, the file transfer was initiated by the command,
GET KERMTEST1
This command is a request to the mini KERMIT to send the file KERMTEST1.
The packets were recorded during the transfer by the micro KERMIT debug
facility, which outputs the contents of all packets, sent and received, to
the printer. Each packet is prefixed with either TX: or RX: when sent to the
printer to indicate whether the packet is being transmitted or received.
The packets sent were as follows:
(a) TX:+ I~> @-`&18<OD>
(b) RX:, Yn% @-`&1~_<OD>
(c) TX:, RKERMTEST1[<OD>
(d) RX:, Sn% @-`&1~Y<OD>
(e) TX:+ Y~> @-`&1H<OD>
(f) RX:+!FKERMTEST!<OD>
(g) TX:`!Y?<OD>
(h) RX:z"Dthis is a test file to show`M`Jwhat packets look like when`M`J
data is being transmitted(<OD>
(i) TX:`"Y@<OD>
(j) RX:6`D by `M`JKERMIT.`M`JM<OD>
(k) TX:``YA<OD>
(l) RX:`$ZC<OD>
(m) TX:`$YB<OD>
(n) RX:`%B,<OD>
(o) TX:`%YC<OD>
(p) TX:$ GF4<OD>
(q) RX:` Y><OD>
The first three characters of each packet make up the header and indicate
the size of the packet, the packet number, and the type of the packet,
respectively. The <OD> at the end of each packet is the end-of-packet
indicator (in this case a carriage return). The character immediately before
the <OD> is a checksum character. (The algorithm used for coding the
checksum can be found in reference 1.)
An Introduction to Kermit Page 5
The characters between the header and the checksum character make up the
data field.
The packet types used in this transfer, indicated by the third character of
the packet, were as follows:
I init-info.
Y acknowledgment
R R type
S send-init.
F file header
D data
Z end-of-file
B end-of-transfer
G KERMIT command
Packet (a), an init-info packet, was sent by the micro prior to sending the
request for a file. The mini acknowledged this packet in the usual way. The
exchange of these two packets is necessary to establish what facilities each
KERMIT has.
Packet (c) was the request from the micro to the mini for the file KERMTEST1
and is an R type packet. The mini initiated the file transfer by sending
a send-init packet, packet (d), which the micro in turn acknowledged. (Note:
packets (a) and (b) are very similar to packets (d) and (e). In both cases
information was being exchanged about the facilities that each KERMIT had to
offer. See reference 1 for more details.)
From packet (f) to packet (o) the pattern of 'receive data then acknowledge
it' was repeated until the transfer was complete. Packets (h) and (j)
contain the actual contents of the file being transferred. The '#M#J' string
in the data field of these packets indicate the carriage returns and line
feeds in the file. The reason for this representation is that the KERMIT
protocol only allows printable characters to be used in packets (i.e.
characters with ASCII values between 32 and 126 inclusive).
Prior to the start of the file transfer (packets (a) to (c)), the packet
number remained at 0 (represented by a space). After this however, the
packet number was incremented by 1 for each packet that was successfully
transferred. The acknowledgment packets from the micro have the same packet
number as the packet that was being acknowledged. The packet number is coded
into a single character, based on ASCII values, according to the algorithm
set down in reference 1.
Packets (l) and (n) were sent to signify the end-of-file and end-of-transfer
respectively and contain no data.
Packet (p) was not part of the file transfer, but was a KERMIT command
packet, which resulted from the FINISH command given to the micro KERMIT.
The data field of the KERMIT command packet contained a single letter
command, in this case an F, indicating to the mini KERMIT that it was to
shut down its server. Packet (q) was an acknowledgment to this command.
Note that the packet number was set back to 0 since these two packets were
not part of the file transfer.
An Introduction to Kermit Page 6
APPENDIX B : REFERENCES
[1] KERMIT Protocol Manual (Sixth Edition). Frank da Cruz, Columbia
University Center for Computing Activities New York, N.Y. 10027.
The same information is covered in a more informal way, with far more
in the way of explanation and example, in
"Kermit : A File Transfer Protocol" by Frank da Cruz (pub. Digital Press)
APPENDIX C : WHERE TO GET KERMIT
Kermit programs are available on many bulletin board systems and from user
groups. There are a few centres that can provide all known implementations,
as follows:
a. World-Wide Distribution
Kermit Distribution
Columbia University Center for Computing Activities
7th Floor
612 West 115th Street
New York
NY 10025
United States
b. Distribution in the UK and Ireland only
Kermit Distribution
Department of Computing
Computer Centre
Lancaster University
Lancaster LA1 4YW
United Kingdom
An Introduction to Kermit Page 7
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KERM| 000001d0 49 54 20 20 69 73 20 74 68 65 20 6e 61 6d 65 20 |IT is the name | 000001e0 6f 66 20 20 61 20 20 66 69 6c 65 20 20 74 72 61 |of a file tra| 000001f0 6e 73 66 65 72 20 20 70 72 6f 74 6f 63 6f 6c 20 |nsfer protocol | 00000200 20 64 65 76 65 6c 6f 70 65 64 20 20 61 74 20 20 | developed at | 00000210 43 6f 6c 75 6d 62 69 61 0d 0a 20 20 55 6e 69 76 |Columbia.. Univ| 00000220 65 72 73 69 74 79 20 43 65 6e 74 65 72 20 66 6f |ersity Center fo| 00000230 72 20 43 6f 6d 70 75 74 69 6e 67 20 41 63 74 69 |r Computing Acti| 00000240 76 69 74 69 65 73 20 20 28 43 55 43 43 41 29 20 |vities (CUCCA) | 00000250 69 6e 20 4e 65 77 20 59 6f 72 6b 2e 20 20 54 68 |in New York. 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The link betw| 000003d0 65 65 6e 20 20 74 68 65 20 20 74 77 6f 20 20 6d |een the two m| 000003e0 61 63 68 69 6e 65 73 20 20 6e 65 65 64 20 20 6f |achines need o| 000003f0 6e 6c 79 20 62 65 20 61 0d 0a 20 20 73 74 61 6e |nly be a.. stan| 00000400 64 61 72 64 20 20 61 73 79 6e 63 68 72 6f 6e 6f |dard asynchrono| 00000410 75 73 20 20 63 6f 6d 6d 75 6e 69 63 61 74 69 6f |us communicatio| 00000420 6e 73 20 20 6c 69 6e 65 2c 20 20 6f 66 20 20 74 |ns line, of t| 00000430 68 65 20 20 6b 69 6e 64 20 74 68 61 74 20 69 73 |he kind that is| 00000440 20 75 73 65 64 20 74 6f 0d 0a 20 20 61 74 74 61 | used to.. atta| 00000450 63 68 20 61 20 74 65 72 6d 69 6e 61 6c 20 74 6f |ch a terminal to| 00000460 20 61 20 63 65 6e 74 72 61 6c 20 63 6f 6d 70 75 | a central compu| 00000470 74 65 72 2e 0d 0a 0d 0a 20 20 43 55 43 43 41 20 |ter..... 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Many pe| 00000550 6f 70 6c 65 20 20 68 61 76 65 20 69 6d 70 6c 65 |ople have imple| 00000560 6d 65 6e 74 65 64 0d 0a 20 20 76 65 72 73 69 6f |mented.. versio| 00000570 6e 73 20 20 6f 66 20 20 4b 45 52 4d 49 54 20 20 |ns of KERMIT | 00000580 6f 6e 20 20 6d 61 6e 79 20 20 64 69 66 66 65 72 |on many differ| 00000590 65 6e 74 20 20 6d 61 63 68 69 6e 65 73 3b 20 20 |ent machines; | 000005a0 6d 69 63 72 6f 2d 63 6f 6d 70 75 74 65 72 2c 20 |micro-computer, | 000005b0 20 6d 69 6e 69 2d 0d 0a 20 20 63 6f 6d 70 75 74 | mini-.. comput| 000005c0 65 72 20 61 6e 64 20 6d 61 69 6e 66 72 61 6d 65 |er and mainframe| 000005d0 20 76 65 72 73 69 6f 6e 73 20 68 61 76 65 20 62 | versions have b| 000005e0 65 65 6e 20 77 72 69 74 74 65 6e 2e 0d 0a 0d 0a |een written.....| 000005f0 0d 0a 0d 0a 0d 0a 20 20 32 2e 20 42 41 53 49 43 |...... 2. BASIC| 00000600 20 50 52 49 4e 43 49 50 4c 45 53 0d 0a 0d 0a 0d | PRINCIPLES.....| 00000610 0a 20 20 54 68 65 20 63 6f 6d 70 6f 6e 65 6e 74 |. The component| 00000620 73 20 72 65 71 75 69 72 65 64 20 74 6f 20 74 72 |s required to tr| 00000630 61 6e 73 66 65 72 20 61 20 20 66 69 6c 65 20 20 |ansfer a file | 00000640 62 65 74 77 65 65 6e 20 20 74 77 6f 20 20 63 6f |between two co| 00000650 6d 70 75 74 65 72 73 2c 20 20 75 73 69 6e 67 0d |mputers, using.| 00000660 0a 20 20 4b 45 52 4d 49 54 2c 20 20 61 72 65 20 |. KERMIT, are | 00000670 74 68 65 20 74 77 6f 20 63 6f 6d 70 75 74 65 72 |the two computer| 00000680 73 2c 20 20 65 61 63 68 20 20 77 69 74 68 20 74 |s, each with t| 00000690 68 65 69 72 20 6f 77 6e 20 4b 45 52 4d 49 54 20 |heir own KERMIT | 000006a0 70 72 6f 67 72 61 6d 2c 20 20 61 6e 64 20 61 0d |program, and a.| 000006b0 0a 20 20 64 61 74 61 20 63 6f 6d 6d 75 6e 69 63 |. data communic| 000006c0 61 74 69 6f 6e 73 20 6c 69 6e 65 20 6a 6f 69 6e |ations line join| 000006d0 69 6e 67 20 74 68 65 6d 20 62 6f 74 68 20 74 6f |ing them both to| 000006e0 67 65 74 68 65 72 2e 0d 0a 0d 0a 20 20 4f 6e 65 |gether..... One| 000006f0 20 6f 66 20 74 68 65 20 4b 45 52 4d 49 54 20 70 | of the KERMIT p| 00000700 72 6f 67 72 61 6d 73 20 20 77 69 6c 6c 20 20 72 |rograms will r| 00000710 75 6e 20 20 6f 6e 20 74 68 65 20 6c 6f 63 61 6c |un on the local| 00000720 20 6d 61 63 68 69 6e 65 20 75 6e 64 65 72 20 74 | machine under t| 00000730 68 65 20 64 69 72 65 63 74 0d 0a 20 20 63 6f 6e |he direct.. con| 00000740 74 72 6f 6c 20 6f 66 20 74 68 65 20 75 73 65 72 |trol of the user| 00000750 2e 20 20 54 68 69 73 20 6d 61 63 68 69 6e 65 20 |. This machine | 00000760 77 69 6c 6c 20 6e 6f 72 6d 61 6c 6c 79 20 62 65 |will normally be| 00000770 20 61 20 6d 69 63 72 6f 63 6f 6d 70 75 74 65 72 | a microcomputer| 00000780 2c 20 61 6e 64 20 69 74 73 0d 0a 20 20 4b 45 52 |, and its.. KER| 00000790 4d 49 54 20 70 72 6f 67 72 61 6d 20 77 69 6c 6c |MIT program will| 000007a0 20 68 61 76 65 20 73 6f 6d 65 20 66 6f 72 6d 20 | have some form | 000007b0 6f 66 20 74 65 72 6d 69 6e 61 6c 20 65 6d 75 6c |of terminal emul| 000007c0 61 74 69 6f 6e 20 63 61 70 61 62 69 6c 69 74 79 |ation capability| 000007d0 20 74 6f 20 61 6c 6c 6f 77 0d 0a 20 20 69 74 20 | to allow.. it | 000007e0 74 6f 20 6c 6f 67 2d 6f 6e 20 74 6f 2c 20 61 6e |to log-on to, an| 000007f0 64 20 69 6e 74 65 72 61 63 74 20 77 69 74 68 20 |d interact with | 00000800 74 68 65 20 6f 74 68 65 72 20 6d 61 63 68 69 6e |the other machin| 00000810 65 20 2d 20 74 68 65 20 72 65 6d 6f 74 65 20 63 |e - the remote c| 00000820 6f 6d 70 75 74 65 72 2e 0d 0a 0d 0a 20 20 54 68 |omputer..... Th| 00000830 65 20 72 65 6d 6f 74 65 20 6d 61 63 68 69 6e 65 |e remote machine| 00000840 2c 20 20 75 73 75 61 6c 6c 79 20 61 20 20 6d 61 |, usually a ma| 00000850 69 6e 66 72 61 6d 65 20 20 6f 72 20 6d 69 6e 69 |inframe or mini| 00000860 2c 20 20 77 69 6c 6c 20 61 6c 73 6f 20 68 61 76 |, will also hav| 00000870 65 20 61 20 4b 45 52 4d 49 54 0d 0a 20 20 70 72 |e a KERMIT.. pr| 00000880 6f 67 72 61 6d 2c 20 20 74 6f 20 77 68 69 63 68 |ogram, to which| 00000890 20 79 6f 75 20 63 61 6e 20 74 79 70 65 20 63 6f | you can type co| 000008a0 6d 6d 61 6e 64 73 20 20 66 72 6f 6d 20 79 6f 75 |mmands from you| 000008b0 72 20 6d 69 63 72 6f 20 75 73 69 6e 67 20 69 74 |r micro using it| 000008c0 73 20 74 65 72 6d 69 6e 61 6c 0d 0a 20 20 65 6d |s terminal.. em| 000008d0 75 6c 61 74 69 6f 6e 20 66 61 63 69 6c 69 74 79 |ulation facility| 000008e0 2e 0d 0a 0d 0a 20 20 54 68 65 20 63 6f 6d 6d 75 |..... The commu| 000008f0 6e 69 63 61 74 69 6f 6e 20 6c 69 6e 6b 20 62 65 |nication link be| 00000900 74 77 65 65 6e 20 74 68 65 20 20 74 77 6f 20 20 |tween the two | 00000910 63 6f 6d 70 75 74 65 72 73 20 20 63 61 6e 20 20 |computers can | 00000920 62 65 20 6d 6f 72 65 20 6f 72 20 6c 65 73 73 20 |be more or less | 00000930 61 6e 79 0d 0a 20 20 61 73 79 6e 63 68 72 6f 6e |any.. asynchron| 00000940 6f 75 73 20 20 28 74 65 72 6d 69 6e 61 6c 29 20 |ous (terminal) | 00000950 20 6c 69 6e 65 2e 20 20 4b 65 72 6d 69 74 20 72 | line. Kermit r| 00000960 65 71 75 69 72 65 73 20 74 68 61 74 20 61 20 43 |equires that a C| 00000970 4f 4e 54 52 4f 4c 2d 41 20 20 63 68 61 72 61 63 |ONTROL-A charac| 00000980 74 65 72 0d 0a 20 20 63 61 6e 20 67 65 74 20 74 |ter.. can get t| 00000990 68 72 6f 75 67 68 20 74 68 65 20 63 6f 6d 6d 75 |hrough the commu| 000009a0 6e 69 63 61 74 69 6f 6e 73 20 65 71 75 69 70 6d |nications equipm| 000009b0 65 6e 74 2c 20 20 73 6f 20 79 6f 75 20 6d 61 79 |ent, so you may| 000009c0 20 6e 65 65 64 20 74 6f 20 61 64 6a 75 73 74 20 | need to adjust | 000009d0 74 68 65 0d 0a 20 20 63 68 61 72 61 63 74 65 72 |the.. character| 000009e0 69 73 74 69 63 73 20 6f 66 20 74 68 65 20 6c 69 |istics of the li| 000009f0 6e 65 20 74 6f 20 61 6c 6c 6f 77 20 74 68 69 73 |ne to allow this| 00000a00 2e 0d 0a 0d 0a 0d 0a 20 20 41 6e 20 49 6e 74 72 |....... An Intr| 00000a10 6f 64 75 63 74 69 6f 6e 20 74 6f 20 4b 65 72 6d |oduction to Kerm| 00000a20 69 74 20 20 20 20 20 20 20 20 20 20 20 20 20 20 |it | 00000a30 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | 00000a40 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 50 | P| 00000a50 61 67 65 20 31 0d 0a 0d 0a 0d 0a 0d 0a 0d 0a 0d |age 1...........| 00000a60 0a 20 20 41 20 74 79 70 69 63 61 6c 20 4b 45 52 |. A typical KER| 00000a70 4d 49 54 20 73 65 73 73 69 6f 6e 20 77 6f 75 6c |MIT session woul| 00000a80 64 20 63 6f 6e 73 69 73 74 20 6f 66 20 74 68 65 |d consist of the| 00000a90 20 66 6f 6c 6c 6f 77 69 6e 67 20 73 74 65 70 73 | following steps| 00000aa0 3a 0d 0a 0d 0a 20 20 31 2e 20 20 54 68 65 20 6c |:.... 1. The l| 00000ab0 6f 63 61 6c 20 28 6d 69 63 72 6f 29 20 4b 45 52 |ocal (micro) KER| 00000ac0 4d 49 54 20 70 72 6f 67 72 61 6d 20 20 69 73 20 |MIT program is | 00000ad0 20 65 6e 74 65 72 65 64 20 20 69 6e 20 20 74 68 | entered in th| 00000ae0 65 20 73 61 6d 65 20 77 61 79 20 74 68 61 74 20 |e same way that | 00000af0 61 6e 79 0d 0a 20 20 20 20 20 20 6f 74 68 65 72 |any.. other| 00000b00 20 70 72 6f 67 72 61 6d 20 69 73 20 69 6e 69 74 | program is init| 00000b10 69 61 74 65 64 2e 0d 0a 0d 0a 20 20 32 2e 20 20 |iated..... 2. | 00000b20 41 6e 79 20 72 65 71 75 69 72 65 64 20 6c 6f 63 |Any required loc| 00000b30 61 6c 20 63 6f 6e 66 69 67 75 72 61 74 69 6f 6e |al configuration| 00000b40 20 69 73 20 63 61 72 72 69 65 64 20 6f 75 74 2c | is carried out,| 00000b50 20 66 6f 72 20 65 78 61 6d 70 6c 65 20 73 65 74 | for example set| 00000b60 74 69 6e 67 20 74 68 65 0d 0a 20 20 20 20 20 20 |ting the.. | 00000b70 6c 69 6e 65 20 73 70 65 65 64 20 66 6f 72 20 74 |line speed for t| 00000b80 68 65 20 74 65 72 6d 69 6e 61 6c 20 65 6d 75 6c |he terminal emul| 00000b90 61 74 6f 72 2e 0d 0a 0d 0a 20 20 33 2e 20 20 54 |ator..... 3. T| 00000ba0 68 65 20 74 65 72 6d 69 6e 61 6c 20 65 6d 75 6c |he terminal emul| 00000bb0 61 74 6f 72 20 69 73 20 65 6e 74 65 72 65 64 2c |ator is entered,| 00000bc0 20 75 73 75 61 6c 6c 79 20 77 69 74 68 20 74 68 | usually with th| 00000bd0 65 20 63 6f 6d 6d 61 6e 64 20 43 4f 4e 4e 45 43 |e command CONNEC| 00000be0 54 2e 0d 0a 0d 0a 20 20 34 2e 20 20 55 73 69 6e |T..... 4. Usin| 00000bf0 67 20 74 68 65 20 65 6d 75 6c 61 74 6f 72 2c 20 |g the emulator, | 00000c00 20 74 68 65 20 72 65 6d 6f 74 65 20 63 6f 6d 70 | the remote comp| 00000c10 75 74 65 72 20 69 73 20 61 63 63 65 73 73 65 64 |uter is accessed| 00000c20 20 69 6e 20 61 6e 20 69 64 65 6e 74 69 63 61 6c | in an identical| 00000c30 20 77 61 79 0d 0a 20 20 20 20 20 20 74 6f 20 74 | way.. to t| 00000c40 68 65 20 75 73 65 20 6f 66 20 61 20 6e 6f 72 6d |he use of a norm| 00000c50 61 6c 20 74 65 72 6d 69 6e 61 6c 20 61 6e 64 20 |al terminal and | 00000c60 61 6e 20 69 6e 74 65 72 61 63 74 69 76 65 20 73 |an interactive s| 00000c70 65 73 73 69 6f 6e 20 69 73 20 62 65 67 75 6e 2e |ession is begun.| 00000c80 0d 0a 0d 0a 20 20 35 2e 20 20 54 68 65 20 4b 45 |.... 5. The KE| 00000c90 52 4d 49 54 20 70 72 6f 67 72 61 6d 20 6f 6e 20 |RMIT program on | 00000ca0 74 68 65 20 72 65 6d 6f 74 65 20 20 68 6f 73 74 |the remote host| 00000cb0 20 20 63 6f 6d 70 75 74 65 72 20 20 69 73 20 20 | computer is | 00000cc0 65 6e 74 65 72 65 64 2c 20 20 61 6e 64 20 20 61 |entered, and a| 00000cd0 6e 79 0d 0a 20 20 20 20 20 20 6e 65 63 65 73 73 |ny.. necess| 00000ce0 61 72 79 20 63 6f 6e 66 69 67 75 72 61 74 69 6f |ary configuratio| 00000cf0 6e 20 63 6f 6d 6d 61 6e 64 73 20 69 73 73 75 65 |n commands issue| 00000d00 64 2e 0d 0a 0d 0a 20 20 36 2e 20 20 41 20 66 69 |d..... 6. A fi| 00000d10 6c 65 20 74 72 61 6e 73 66 65 72 20 63 6f 6d 6d |le transfer comm| 00000d20 61 6e 64 20 69 73 20 69 73 73 75 65 64 20 20 74 |and is issued t| 00000d30 6f 20 20 74 68 65 20 20 72 65 6d 6f 74 65 20 4b |o the remote K| 00000d40 45 52 4d 49 54 2c 20 20 64 65 70 65 6e 64 69 6e |ERMIT, dependin| 00000d50 67 20 6f 6e 0d 0a 20 20 20 20 20 20 77 68 65 74 |g on.. whet| 00000d60 68 65 72 20 79 6f 75 20 69 6e 74 65 6e 64 20 74 |her you intend t| 00000d70 6f 20 73 65 6e 64 20 61 20 66 69 6c 65 20 74 6f |o send a file to| 00000d80 20 74 68 65 20 20 72 65 6d 6f 74 65 20 20 63 6f | the remote co| 00000d90 6d 70 75 74 65 72 20 28 69 6e 20 74 68 69 73 20 |mputer (in this | 00000da0 63 61 73 65 0d 0a 20 20 20 20 20 20 79 6f 75 20 |case.. you | 00000db0 74 65 6c 6c 20 74 68 65 20 72 65 6d 6f 74 65 20 |tell the remote | 00000dc0 4b 45 52 4d 49 54 20 74 6f 20 52 45 43 45 49 56 |KERMIT to RECEIV| 00000dd0 45 29 2c 20 6f 72 20 61 73 6b 20 69 74 20 74 6f |E), or ask it to| 00000de0 20 73 65 6e 64 20 61 20 66 69 6c 65 20 74 6f 20 | send a file to | 00000df0 79 6f 75 72 0d 0a 20 20 20 20 20 20 6c 6f 63 61 |your.. loca| 00000e00 6c 20 63 6f 6d 70 75 74 65 72 20 28 69 6e 20 77 |l computer (in w| 00000e10 68 69 63 68 20 63 61 73 65 20 79 6f 75 20 74 65 |hich case you te| 00000e20 6c 6c 20 74 68 65 20 72 65 6d 6f 74 65 20 4b 45 |ll the remote KE| 00000e30 52 4d 49 54 20 74 6f 20 53 45 4e 44 29 2e 0d 0a |RMIT to SEND)...| 00000e40 0d 0a 20 20 37 2e 20 20 54 68 65 20 74 65 72 6d |.. 7. The term| 00000e50 69 6e 61 6c 20 65 6d 75 6c 61 74 6f 72 20 6f 6e |inal emulator on| 00000e60 20 74 68 65 20 20 6c 6f 63 61 6c 20 20 4b 45 52 | the local KER| 00000e70 4d 49 54 20 20 69 73 20 20 74 68 65 6e 20 65 78 |MIT is then ex| 00000e80 69 74 65 64 20 62 79 20 75 73 65 20 6f 66 20 61 |ited by use of a| 00000e90 0d 0a 20 20 20 20 20 20 27 6c 6f 63 61 6c 20 20 |.. 'local | 00000ea0 65 73 63 61 70 65 27 20 20 20 63 68 61 72 61 63 |escape' charac| 00000eb0 74 65 72 20 20 73 65 71 75 65 6e 63 65 2e 20 20 |ter sequence. | 00000ec0 54 68 69 73 20 70 75 74 73 20 74 68 65 20 6c 6f |This puts the lo| 00000ed0 63 61 6c 20 70 72 6f 67 72 61 6d 20 62 61 63 6b |cal program back| 00000ee0 0d 0a 20 20 20 20 20 20 69 6e 74 6f 20 74 68 65 |.. into the| 00000ef0 20 63 6f 6d 6d 61 6e 64 20 6d 6f 64 65 20 6f 72 | command mode or| 00000f00 69 67 69 6e 61 6c 6c 79 20 65 6e 74 65 72 65 64 |iginally entered| 00000f10 20 69 6e 20 73 74 65 70 20 31 2e 0d 0a 0d 0a 20 | in step 1..... | 00000f20 20 38 2e 20 20 41 20 6c 6f 63 61 6c 20 66 69 6c | 8. A local fil| 00000f30 65 20 74 72 61 6e 73 66 65 72 20 63 6f 6d 6d 61 |e transfer comma| 00000f40 6e 64 20 20 69 73 20 20 69 73 73 75 65 64 2e 20 |nd is issued. | 00000f50 20 54 68 69 73 20 77 69 6c 6c 20 62 65 20 53 45 | This will be SE| 00000f60 4e 44 20 6f 72 20 52 45 43 45 49 56 45 0d 0a 20 |ND or RECEIVE.. | 00000f70 20 20 20 20 20 64 65 70 65 6e 64 69 6e 67 20 20 | depending | 00000f80 6f 6e 20 74 68 65 20 64 69 72 65 63 74 69 6f 6e |on the direction| 00000f90 20 74 68 65 20 74 72 61 6e 73 66 65 72 20 69 73 | the transfer is| 00000fa0 20 74 6f 20 20 74 61 6b 65 2e 20 20 28 4e 61 74 | to take. (Nat| 00000fb0 75 72 61 6c 6c 79 2c 20 20 74 68 69 73 0d 0a 20 |urally, this.. | 00000fc0 20 20 20 20 20 63 6f 6d 6d 61 6e 64 20 77 69 6c | command wil| 00000fd0 6c 20 62 65 20 74 68 65 20 6f 70 70 6f 73 69 74 |l be the opposit| 00000fe0 65 20 6f 66 20 74 68 61 74 20 69 73 73 75 65 64 |e of that issued| 00000ff0 20 74 6f 20 74 68 65 20 72 65 6d 6f 74 65 20 6d | to the remote m| 00001000 61 63 68 69 6e 65 2e 29 0d 0a 0d 0a 20 20 39 2e |achine.).... 9.| 00001010 20 20 54 68 65 20 66 69 6c 65 20 74 72 61 6e 73 | The file trans| 00001020 66 65 72 20 77 69 6c 6c 20 70 72 6f 63 65 65 64 |fer will proceed| 00001030 20 20 75 6e 64 65 72 20 20 74 68 65 20 20 63 6f | under the co| 00001040 6e 74 72 6f 6c 20 20 6f 66 20 20 74 68 65 20 20 |ntrol of the | 00001050 74 77 6f 20 4b 45 52 4d 49 54 0d 0a 20 20 20 20 |two KERMIT.. | 00001060 20 20 70 72 6f 67 72 61 6d 73 20 20 75 6e 74 69 | programs unti| 00001070 6c 20 20 74 68 65 20 20 66 69 6c 65 20 20 68 61 |l the file ha| 00001080 73 20 20 62 65 65 6e 20 63 6f 6d 70 6c 65 74 65 |s been complete| 00001090 6c 79 20 74 72 61 6e 73 66 65 72 72 65 64 20 28 |ly transferred (| 000010a0 6f 72 20 61 20 66 61 74 61 6c 0d 0a 20 20 20 20 |or a fatal.. | 000010b0 20 20 65 72 72 6f 72 20 68 61 73 20 6f 63 63 75 | error has occu| 000010c0 72 72 65 64 29 2e 20 20 54 68 65 20 6c 6f 63 61 |rred). The loca| 000010d0 6c 20 4b 45 52 4d 49 54 20 77 69 6c 6c 20 74 68 |l KERMIT will th| 000010e0 65 6e 20 72 65 74 75 72 6e 20 74 6f 20 63 6f 6d |en return to com| 000010f0 6d 61 6e 64 20 6d 6f 64 65 2e 0d 0a 0d 0a 20 20 |mand mode..... | 00001100 31 30 2e 20 55 73 69 6e 67 20 74 68 65 20 74 65 |10. Using the te| 00001110 72 6d 69 6e 61 6c 20 65 6d 75 6c 61 74 6f 72 20 |rminal emulator | 00001120 70 61 72 74 20 20 6f 66 20 20 74 68 65 20 20 6c |part of the l| 00001130 6f 63 61 6c 20 20 4b 45 52 4d 49 54 2c 20 20 74 |ocal KERMIT, t| 00001140 68 65 20 20 68 6f 73 74 20 20 69 73 0d 0a 20 20 |he host is.. | 00001150 20 20 20 20 61 63 63 65 73 73 65 64 2c 20 61 6e | accessed, an| 00001160 64 20 74 68 65 20 72 65 6d 6f 74 65 20 4b 45 52 |d the remote KER| 00001170 4d 49 54 20 63 6c 6f 73 65 64 20 64 6f 77 6e 2e |MIT closed down.| 00001180 20 20 54 68 65 20 69 6e 74 65 72 61 63 74 69 76 | The interactiv| 00001190 65 20 73 65 73 73 69 6f 6e 20 69 73 0d 0a 20 20 |e session is.. | 000011a0 20 20 20 20 74 68 65 6e 20 65 6e 64 65 64 20 61 | then ended a| 000011b0 6e 64 20 74 68 65 20 20 6c 6f 63 61 6c 20 20 4b |nd the local K| 000011c0 45 52 4d 49 54 20 74 65 72 6d 69 6e 61 74 65 64 |ERMIT terminated| 000011d0 3b 20 20 74 68 65 20 4b 45 52 4d 49 54 20 73 65 |; the KERMIT se| 000011e0 73 73 69 6f 6e 20 69 73 20 6e 6f 77 0d 0a 20 20 |ssion is now.. | 000011f0 20 20 20 20 63 6f 6d 70 6c 65 74 65 2e 0d 0a 0d | complete....| 00001200 0a 20 20 49 66 20 74 68 65 72 65 20 61 72 65 20 |. If there are | 00001210 73 65 76 65 72 61 6c 20 66 69 6c 65 73 20 20 74 |several files t| 00001220 6f 20 20 62 65 20 20 74 72 61 6e 73 66 65 72 72 |o be transferr| 00001230 65 64 20 20 62 65 74 77 65 65 6e 20 20 74 68 65 |ed between the| 00001240 20 6c 6f 63 61 6c 20 61 6e 64 20 68 6f 73 74 0d | local and host.| 00001250 0a 20 20 63 6f 6d 70 75 74 65 72 73 20 73 74 65 |. computers ste| 00001260 70 73 20 36 20 74 6f 20 39 20 61 62 6f 76 65 20 |ps 6 to 9 above | 00001270 77 69 6c 6c 20 68 61 76 65 20 74 6f 20 62 65 20 |will have to be | 00001280 72 65 70 65 61 74 65 64 2e 0d 0a 0d 0a 20 20 45 |repeated..... E| 00001290 76 65 72 79 20 74 69 6d 65 20 61 20 63 6f 6e 74 |very time a cont| 000012a0 72 6f 6c 20 63 6f 6d 6d 61 6e 64 20 69 73 20 74 |rol command is t| 000012b0 6f 20 62 65 20 69 73 73 75 65 64 20 74 6f 20 74 |o be issued to t| 000012c0 68 65 20 72 65 6d 6f 74 65 20 4b 45 52 4d 49 54 |he remote KERMIT| 000012d0 2c 20 74 68 65 20 6c 6f 63 61 6c 0d 0a 20 20 4b |, the local.. K| 000012e0 45 52 4d 49 54 20 6d 75 73 74 20 62 65 20 73 77 |ERMIT must be sw| 000012f0 69 74 63 68 65 64 20 69 6e 74 6f 20 69 74 73 20 |itched into its | 00001300 74 65 72 6d 69 6e 61 6c 20 65 6d 75 6c 61 74 69 |terminal emulati| 00001310 6f 6e 20 6d 6f 64 65 2e 20 54 6f 20 73 74 72 65 |on mode. To stre| 00001320 61 6d 6c 69 6e 65 20 74 68 69 73 0d 0a 20 20 70 |amline this.. p| 00001330 72 6f 63 65 73 73 2c 20 20 73 6f 6d 65 20 72 65 |rocess, some re| 00001340 6d 6f 74 65 20 4b 45 52 4d 49 54 73 20 63 61 6e |mote KERMITs can| 00001350 20 20 62 65 20 20 72 75 6e 20 20 69 6e 20 53 45 | be run in SE| 00001360 52 56 45 52 20 6d 6f 64 65 2e 20 20 41 20 4b 45 |RVER mode. A KE| 00001370 52 4d 49 54 20 73 65 72 76 65 72 0d 0a 20 20 77 |RMIT server.. w| 00001380 69 6c 6c 20 61 63 63 65 70 74 20 63 6f 6d 6d 61 |ill accept comma| 00001390 6e 64 73 20 73 65 6e 74 20 62 79 20 74 68 65 20 |nds sent by the | 000013a0 6c 6f 63 61 6c 20 4b 45 52 4d 49 54 20 61 63 72 |local KERMIT acr| 000013b0 6f 73 73 20 74 68 65 20 63 6f 6d 6d 75 6e 69 63 |oss the communic| 000013c0 61 74 69 6f 6e 73 20 6c 69 6e 6b 0d 0a 20 20 77 |ations link.. w| 000013d0 69 74 68 6f 75 74 20 74 68 65 20 6c 6f 63 61 6c |ithout the local| 000013e0 20 4b 45 52 4d 49 54 20 68 61 76 69 6e 67 20 74 | KERMIT having t| 000013f0 6f 20 73 77 69 74 63 68 20 74 6f 20 20 74 65 72 |o switch to ter| 00001400 6d 69 6e 61 6c 20 65 6d 75 6c 61 74 69 6f 6e 20 |minal emulation | 00001410 6d 6f 64 65 2e 20 20 54 68 69 73 0d 0a 20 20 6d |mode. This.. m| 00001420 65 61 6e 73 20 20 74 68 61 74 20 74 68 65 20 72 |eans that the r| 00001430 65 6d 6f 74 65 20 4b 45 52 4d 49 54 20 63 61 6e |emote KERMIT can| 00001440 20 62 65 20 63 6f 6e 74 72 6f 6c 6c 65 64 20 62 | be controlled b| 00001450 79 20 20 63 6f 6d 6d 61 6e 64 73 20 20 67 69 76 |y commands giv| 00001460 65 6e 20 20 74 6f 20 20 74 68 65 0d 0a 20 20 6c |en to the.. l| 00001470 6f 63 61 6c 20 4b 45 52 4d 49 54 2e 0d 0a 0d 0a |ocal KERMIT.....| 00001480 20 20 4e 6f 74 20 61 6c 6c 20 4b 45 52 4d 49 54 | Not all KERMIT| 00001490 20 70 72 6f 67 72 61 6d 73 20 6f 66 66 65 72 20 | programs offer | 000014a0 74 68 65 20 73 61 6d 65 20 66 61 63 69 6c 69 74 |the same facilit| 000014b0 69 65 73 2c 20 73 6f 20 74 68 65 20 61 70 70 72 |ies, so the appr| 000014c0 6f 70 72 69 61 74 65 20 6d 61 6e 75 61 6c 0d 0a |opriate manual..| 000014d0 20 20 73 68 6f 75 6c 64 20 61 6c 77 61 79 73 20 | should always | 000014e0 62 65 20 63 68 65 63 6b 65 64 20 74 6f 20 20 66 |be checked to f| 000014f0 69 6e 64 20 6f 75 74 20 77 68 61 74 20 66 61 63 |ind out what fac| 00001500 69 6c 69 74 69 65 73 20 74 68 65 20 4b 45 52 4d |ilities the KERM| 00001510 49 54 73 20 62 65 69 6e 67 20 75 73 65 64 0d 0a |ITs being used..| 00001520 20 20 68 61 76 65 2e 20 20 49 74 20 69 73 20 6e | have. It is n| 00001530 6f 20 67 6f 6f 64 2c 20 66 6f 72 20 65 78 61 6d |o good, for exam| 00001540 70 6c 65 2c 20 20 70 75 74 74 69 6e 67 20 61 20 |ple, putting a | 00001550 72 65 6d 6f 74 65 20 4b 45 52 4d 49 54 20 69 6e |remote KERMIT in| 00001560 74 6f 20 73 65 72 76 65 72 20 6d 6f 64 65 0d 0a |to server mode..| 00001570 20 20 69 66 20 74 68 65 20 6c 6f 63 61 6c 20 4b | if the local K| 00001580 45 52 4d 49 54 20 69 73 20 6e 6f 74 20 63 61 70 |ERMIT is not cap| 00001590 61 62 6c 65 20 6f 66 20 63 6f 6e 74 72 6f 6c 6c |able of controll| 000015a0 69 6e 67 20 61 20 4b 45 52 4d 49 54 20 73 65 72 |ing a KERMIT ser| 000015b0 76 65 72 2e 0d 0a 0d 0a 0d 0a 0d 0a 0d 0a 0d 0a |ver.............| 000015c0 0d 0a 0d 0a 20 20 41 6e 20 49 6e 74 72 6f 64 75 |.... An Introdu| 000015d0 63 74 69 6f 6e 20 74 6f 20 4b 65 72 6d 69 74 20 |ction to Kermit | 000015e0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | * 00001600 20 20 20 20 20 20 20 20 20 20 20 20 50 61 67 65 | Page| 00001610 20 32 0d 0a 0d 0a 0d 0a 0d 0a 0d 0a 0d 0a 20 20 | 2............ | 00001620 33 2e 20 41 4e 20 4f 55 54 4c 49 4e 45 20 4f 46 |3. AN OUTLINE OF| 00001630 20 54 48 45 20 50 52 4f 54 4f 43 4f 4c 0d 0a 0d | THE PROTOCOL...| 00001640 0a 0d 0a 20 20 57 68 65 6e 20 69 6e 66 6f 72 6d |... When inform| 00001650 61 74 69 6f 6e 20 69 73 20 62 65 69 6e 67 20 74 |ation is being t| 00001660 72 61 6e 73 66 65 72 72 65 64 20 20 62 65 74 77 |ransferred betw| 00001670 65 65 6e 20 4b 45 52 4d 49 54 20 70 72 6f 67 72 |een KERMIT progr| 00001680 61 6d 73 20 69 74 20 69 73 20 73 65 6e 74 20 69 |ams it is sent i| 00001690 6e 0d 0a 20 20 62 6c 6f 63 6b 73 20 6f 72 20 70 |n.. blocks or p| 000016a0 61 63 6b 65 74 73 2e 20 20 41 20 4b 45 52 4d 49 |ackets. 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Most| 00002500 20 4b 45 52 4d 49 54 20 69 6d 70 6c 65 6d 65 6e | KERMIT implemen| 00002510 74 61 74 69 6f 6e 73 20 77 69 6c 6c 20 61 6c 6c |tations will all| 00002520 6f 77 20 61 20 73 65 72 69 65 73 20 6f 66 20 66 |ow a series of f| 00002530 69 6c 65 73 20 74 6f 0d 0a 20 20 62 65 20 73 65 |iles to.. be se| 00002540 6e 74 20 69 6e 20 61 20 73 69 6e 67 6c 65 20 74 |nt in a single t| 00002550 72 61 6e 73 61 63 74 69 6f 6e 2c 20 20 61 6e 64 |ransaction, and| 00002560 20 74 68 65 20 74 77 6f 20 74 79 70 65 73 20 6f | the two types o| 00002570 66 20 65 6e 64 20 70 61 63 6b 65 74 20 61 72 65 |f end packet are| 00002580 20 6e 65 65 64 65 64 0d 0a 20 20 66 6f 72 20 74 | needed.. for t| 00002590 68 69 73 20 70 75 72 70 6f 73 65 2e 0d 0a 0d 0a |his purpose.....| 000025a0 0d 0a 20 20 28 62 29 20 53 65 72 76 65 72 20 4d |.. (b) Server M| 000025b0 6f 64 65 0d 0a 0d 0a 0d 0a 20 20 54 68 65 20 6f |ode...... The o| 000025c0 72 64 65 72 20 61 6e 64 20 74 79 70 65 20 6f 66 |rder and type of| 000025d0 20 20 70 61 63 6b 65 74 73 20 20 73 65 6e 74 20 | packets sent | 000025e0 20 64 75 72 69 6e 67 20 20 61 20 20 4b 45 52 4d | during a KERM| 000025f0 49 54 20 20 73 65 73 73 69 6f 6e 20 69 73 20 73 |IT session is s| 00002600 6c 69 67 68 74 6c 79 0d 0a 20 20 61 6c 74 65 72 |lightly.. alter| 00002610 65 64 20 20 69 66 20 74 68 65 20 72 65 6d 6f 74 |ed if the remot| 00002620 65 20 4b 45 52 4d 49 54 20 68 61 73 20 62 65 65 |e KERMIT has bee| 00002630 6e 20 70 75 74 20 69 6e 74 6f 20 73 65 72 76 65 |n put into serve| 00002640 72 20 6d 6f 64 65 2e 20 20 46 6f 72 20 20 69 6e |r mode. For in| 00002650 73 74 61 6e 63 65 2c 0d 0a 20 20 74 68 65 20 6c |stance,.. the l| 00002660 6f 63 61 6c 20 4b 45 52 4d 49 54 20 6d 69 67 68 |ocal KERMIT migh| 00002670 74 20 77 61 6e 74 20 74 6f 20 73 65 6e 64 20 61 |t want to send a| 00002680 20 63 6f 6d 6d 61 6e 64 20 74 6f 20 74 68 65 20 | command to the | 00002690 72 65 6d 6f 74 65 20 4b 45 52 4d 49 54 2c 20 70 |remote KERMIT, p| 000026a0 6f 73 73 69 62 6c 79 0d 0a 20 20 74 6f 20 63 68 |ossibly.. to ch| 000026b0 61 6e 67 65 20 73 6f 6d 65 20 70 61 72 61 6d 65 |ange some parame| 000026c0 74 65 72 2e 20 20 54 68 69 73 20 77 6f 75 6c 64 |ter. This would| 000026d0 20 62 65 20 64 6f 6e 65 20 62 79 20 73 65 6e 64 | be done by send| 000026e0 69 6e 67 20 61 20 63 6f 6d 6d 61 6e 64 20 70 61 |ing a command pa| 000026f0 63 6b 65 74 20 74 6f 0d 0a 20 20 74 68 65 20 73 |cket to.. the s| 00002700 65 72 76 65 72 2e 20 20 48 6f 77 65 76 65 72 2c |erver. However,| 00002710 20 20 74 68 65 20 20 6c 6f 63 61 6c 20 61 6e 64 | the local and| 00002720 20 20 72 65 6d 6f 74 65 20 4b 45 52 4d 49 54 73 | remote KERMITs| 00002730 20 6d 61 79 20 6e 6f 74 20 68 61 76 65 20 65 78 | may not have ex| 00002740 63 68 61 6e 67 65 64 0d 0a 20 20 69 6e 66 6f 72 |changed.. infor| 00002750 6d 61 74 69 6f 6e 20 73 75 63 68 20 61 73 20 70 |mation such as p| 00002760 61 63 6b 65 74 20 6c 65 6e 67 74 68 2c 20 65 6e |acket length, en| 00002770 64 2d 6f 66 2d 70 61 63 6b 65 74 20 63 68 61 72 |d-of-packet char| 00002780 61 63 74 65 72 2c 20 20 63 68 65 63 6b 20 73 65 |acter, check se| 00002790 71 75 65 6e 63 65 2c 0d 0a 20 20 65 74 63 2e 20 |quence,.. etc. | 000027a0 20 28 61 6e 64 20 20 65 76 65 6e 20 20 69 66 20 | (and even if | 000027b0 20 74 68 65 79 20 20 68 61 64 2c 20 20 73 6f 6d | they had, som| 000027c0 65 20 20 70 61 72 61 6d 65 74 65 72 73 20 20 20 |e parameters | 000027d0 6d 69 67 68 74 20 20 20 63 68 61 6e 67 65 20 20 |might change | 000027e0 62 65 74 77 65 65 6e 0d 0a 20 20 74 72 61 6e 73 |between.. trans| 000027f0 61 63 74 69 6f 6e 73 29 2e 20 20 54 6f 20 20 6f |actions). To o| 00002800 76 65 72 63 6f 6d 65 20 74 68 69 73 20 70 6f 74 |vercome this pot| 00002810 65 6e 74 69 61 6c 20 70 72 6f 62 6c 65 6d 2c 20 |ential problem, | 00002820 61 6e 20 69 6e 69 74 2d 69 6e 66 6f 20 20 70 61 |an init-info pa| 00002830 63 6b 65 74 20 69 73 0d 0a 20 20 73 65 6e 74 20 |cket is.. sent | 00002840 74 6f 20 74 68 65 20 20 73 65 72 76 65 72 20 20 |to the server | 00002850 70 72 69 6f 72 20 20 74 6f 20 20 6d 6f 73 74 20 |prior to most | 00002860 20 74 72 61 6e 73 61 63 74 69 6f 6e 73 2e 20 20 | transactions. | 00002870 54 68 69 73 20 20 74 79 70 65 20 6f 66 20 70 61 |This type of pa| 00002880 63 6b 65 74 20 69 73 0d 0a 20 20 65 78 61 63 74 |cket is.. exact| 00002890 6c 79 20 6c 69 6b 65 20 74 68 65 20 69 6e 69 74 |ly like the init| 000028a0 69 61 6c 69 73 61 74 69 6f 6e 20 70 61 63 6b 65 |ialisation packe| 000028b0 74 20 61 6e 64 20 69 73 20 61 63 6b 6e 6f 77 6c |t and is acknowl| 000028c0 65 64 67 65 64 20 69 6e 20 74 68 65 20 20 73 61 |edged in the sa| 000028d0 6d 65 20 77 61 79 2c 0d 0a 20 20 62 75 74 20 64 |me way,.. but d| 000028e0 6f 65 73 20 6e 6f 74 20 63 61 75 73 65 20 74 68 |oes not cause th| 000028f0 65 20 73 65 72 76 65 72 20 74 6f 20 74 68 69 6e |e server to thin| 00002900 6b 20 74 68 61 74 20 69 74 20 69 73 20 61 62 6f |k that it is abo| 00002910 75 74 20 74 6f 20 62 65 20 73 65 6e 74 20 61 20 |ut to be sent a | 00002920 66 69 6c 65 2e 0d 0a 0d 0a 20 20 57 68 65 6e 20 |file..... When | 00002930 61 20 6c 6f 63 61 6c 20 4b 45 52 4d 49 54 2c 20 |a local KERMIT, | 00002940 20 77 68 69 63 68 20 20 69 73 20 69 6e 20 20 63 | which is in c| 00002950 6f 6e 74 72 6f 6c 20 20 6f 66 20 61 20 20 72 65 |ontrol of a re| 00002960 6d 6f 74 65 20 4b 45 52 4d 49 54 2c 20 20 77 69 |mote KERMIT, wi| 00002970 73 68 65 73 20 74 6f 0d 0a 20 20 72 65 63 65 69 |shes to.. recei| 00002980 76 65 20 20 61 20 20 66 69 6c 65 20 28 75 73 75 |ve a file (usu| 00002990 61 6c 6c 79 20 61 63 68 69 65 76 65 64 20 62 79 |ally achieved by| 000029a0 20 69 73 73 75 69 6e 67 20 74 68 65 20 20 47 45 | issuing the GE| 000029b0 54 20 20 63 6f 6d 6d 61 6e 64 20 74 6f 20 74 68 |T command to th| 000029c0 65 20 6c 6f 63 61 6c 0d 0a 20 20 4b 45 52 4d 49 |e local.. KERMI| 000029d0 54 29 20 69 74 20 73 65 6e 64 73 20 61 6e 20 69 |T) it sends an i| 000029e0 6e 69 74 2d 69 6e 66 6f 20 70 61 63 6b 65 74 20 |nit-info packet | 000029f0 74 68 65 6e 2c 20 20 6f 6e 63 65 20 74 68 61 74 |then, once that| 00002a00 20 68 61 73 20 62 65 65 6e 20 61 63 6b 6e 6f 77 | has been acknow| 00002a10 6c 65 64 67 65 64 2c 0d 0a 20 20 61 6e 20 52 20 |ledged,.. an R | 00002a20 74 79 70 65 20 70 61 63 6b 65 74 2e 20 20 54 68 |type packet. Th| 00002a30 65 20 20 52 20 20 70 61 63 6b 65 74 20 20 77 69 |e R packet wi| 00002a40 6c 6c 20 69 6e 64 69 63 61 74 65 20 74 6f 20 74 |ll indicate to t| 00002a50 68 65 20 73 65 72 76 65 72 20 74 68 61 74 20 69 |he server that i| 00002a60 74 20 69 73 20 74 6f 0d 0a 20 20 73 65 6e 64 20 |t is to.. send | 00002a70 61 20 66 69 6c 65 2c 20 20 74 68 65 20 6e 61 6d |a file, the nam| 00002a80 65 20 6f 66 20 77 68 69 63 68 20 77 69 6c 6c 20 |e of which will | 00002a90 62 65 20 69 6e 20 74 68 65 20 64 61 74 61 20 66 |be in the data f| 00002aa0 69 65 6c 64 20 6f 66 20 74 68 65 20 70 61 63 6b |ield of the pack| 00002ab0 65 74 2e 20 54 68 65 0d 0a 20 20 72 65 6d 6f 74 |et. The.. remot| 00002ac0 65 20 4b 45 52 4d 49 54 20 77 69 6c 6c 20 72 65 |e KERMIT will re| 00002ad0 73 70 6f 6e 64 20 74 6f 20 74 68 69 73 20 72 65 |spond to this re| 00002ae0 71 75 65 73 74 20 69 6e 20 6f 6e 65 20 6f 66 20 |quest in one of | 00002af0 74 77 6f 20 77 61 79 73 2e 20 20 49 66 20 69 74 |two ways. If it| 00002b00 20 63 61 6e 6e 6f 74 0d 0a 20 20 66 69 6e 64 20 | cannot.. find | 00002b10 6f 72 20 61 63 63 65 73 73 20 74 68 65 20 72 65 |or access the re| 00002b20 71 75 65 73 74 65 64 20 66 69 6c 65 2c 20 69 74 |quested file, it| 00002b30 20 77 69 6c 6c 20 73 65 6e 64 20 61 6e 20 20 65 | will send an e| 00002b40 72 72 6f 72 20 20 70 61 63 6b 65 74 20 77 68 69 |rror packet whi| 00002b50 63 68 20 77 69 6c 6c 0d 0a 20 20 63 6f 6e 74 61 |ch will.. conta| 00002b60 69 6e 20 20 61 6e 20 20 61 70 70 72 6f 70 72 69 |in an appropri| 00002b70 61 74 65 20 20 6d 65 73 73 61 67 65 2c 20 6f 74 |ate message, ot| 00002b80 68 65 72 77 69 73 65 2c 20 69 66 20 61 6c 6c 20 |herwise, if all | 00002b90 69 73 20 77 65 6c 6c 2c 20 69 74 20 77 69 6c 6c |is well, it will| 00002ba0 20 73 65 6e 64 20 61 0d 0a 20 20 73 65 6e 64 2d | send a.. send-| 00002bb0 69 6e 69 74 20 70 61 63 6b 65 74 20 61 6e 64 20 |init packet and | 00002bc0 74 68 65 20 74 72 61 6e 73 66 65 72 20 77 69 6c |the transfer wil| 00002bd0 6c 20 63 6f 6e 74 69 6e 75 65 20 61 73 20 69 6e |l continue as in| 00002be0 20 28 61 29 20 61 62 6f 76 65 2e 0d 0a 0d 0a 20 | (a) above..... | 00002bf0 20 46 6f 72 20 74 68 65 20 63 61 73 65 20 77 68 | For the case wh| 00002c00 65 6e 20 74 68 65 20 20 6c 6f 63 61 6c 20 20 4b |en the local K| 00002c10 45 52 4d 49 54 20 20 77 61 6e 74 73 20 20 74 6f |ERMIT wants to| 00002c20 20 20 53 45 4e 44 20 61 20 66 69 6c 65 20 74 6f | SEND a file to| 00002c30 20 61 20 73 65 72 76 65 72 20 74 68 65 0d 0a 20 | a server the.. | 00002c40 20 74 72 61 6e 73 66 65 72 20 70 72 6f 63 65 65 | transfer procee| 00002c50 64 73 20 61 73 20 69 6e 20 28 61 29 20 61 62 6f |ds as in (a) abo| 00002c60 76 65 20 77 69 74 68 6f 75 74 20 74 68 65 20 6e |ve without the n| 00002c70 65 65 64 20 66 6f 72 20 74 68 65 20 69 6e 69 74 |eed for the init| 00002c80 2d 69 6e 66 6f 20 70 61 63 6b 65 74 2e 0d 0a 0d |-info packet....| 00002c90 0a 20 20 4f 6e 63 65 20 61 20 72 65 6d 6f 74 65 |. Once a remote| 00002ca0 20 4b 45 52 4d 49 54 20 69 73 20 20 69 6e 20 20 | KERMIT is in | 00002cb0 73 65 72 76 65 72 20 20 6d 6f 64 65 20 20 69 74 |server mode it| 00002cc0 20 20 77 69 6c 6c 20 20 6f 6e 6c 79 20 72 65 63 | will only rec| 00002cd0 65 69 76 65 20 70 61 63 6b 65 74 73 20 61 73 0d |eive packets as.| 00002ce0 0a 20 20 69 6e 70 75 74 2c 20 73 6f 2c 20 69 6e |. input, so, in| 00002cf0 20 6f 72 64 65 72 20 74 6f 20 72 65 63 6f 6e 6e | order to reconn| 00002d00 65 63 74 20 74 6f 20 74 68 65 20 72 65 6d 6f 74 |ect to the remot| 00002d10 65 20 63 6f 6d 70 75 74 65 72 20 74 6f 20 20 65 |e computer to e| 00002d20 6e 64 20 74 68 65 20 73 65 73 73 69 6f 6e 2c 0d |nd the session,.| 00002d30 0a 20 20 69 74 20 77 69 6c 6c 20 62 65 20 6e 65 |. it will be ne| 00002d40 63 65 73 73 61 72 79 20 74 6f 20 73 68 75 74 20 |cessary to shut | 00002d50 64 6f 77 6e 20 74 68 65 20 73 65 72 76 65 72 20 |down the server | 00002d60 66 69 72 73 74 2e 20 20 20 54 68 69 73 20 69 73 |first. This is| 00002d70 20 64 6f 6e 65 20 62 79 20 74 79 70 69 6e 67 0d | done by typing.| 00002d80 0a 20 20 74 68 65 20 20 46 49 4e 49 53 48 20 63 |. the FINISH c| 00002d90 6f 6d 6d 61 6e 64 20 74 6f 20 74 68 65 20 6c 6f |ommand to the lo| 00002da0 63 61 6c 20 4b 45 52 4d 49 54 2c 20 77 68 69 63 |cal KERMIT, whic| 00002db0 68 20 66 6f 72 63 65 73 20 61 20 63 6f 6d 6d 61 |h forces a comma| 00002dc0 6e 64 20 70 61 63 6b 65 74 20 74 6f 20 62 65 0d |nd packet to be.| 00002dd0 0a 20 20 73 65 6e 74 20 74 6f 20 74 68 65 20 72 |. sent to the r| 00002de0 65 6d 6f 74 65 20 4b 45 52 4d 49 54 20 74 65 6c |emote KERMIT tel| 00002df0 6c 69 6e 67 20 69 74 20 74 6f 20 73 68 75 74 20 |ling it to shut | 00002e00 64 6f 77 6e 20 74 68 65 20 73 65 72 76 65 72 2e |down the server.| 00002e10 0d 0a 0d 0a 0d 0a 0d 0a 0d 0a 0d 0a 0d 0a 0d 0a |................| * 00002e30 0d 0a 0d 0a 0d 0a 0d 0a 0d 0a 20 20 41 6e 20 49 |.......... An I| 00002e40 6e 74 72 6f 64 75 63 74 69 6f 6e 20 74 6f 20 4b |ntroduction to K| 00002e50 65 72 6d 69 74 20 20 20 20 20 20 20 20 20 20 20 |ermit | 00002e60 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | * 00002e80 20 20 50 61 67 65 20 34 0d 0a 0d 0a 0d 0a 0d 0a | Page 4........| 00002e90 0d 0a 0d 0a 20 20 41 50 50 45 4e 44 49 58 20 41 |.... APPENDIX A| 00002ea0 3a 20 41 20 43 4c 4f 53 45 52 20 4c 4f 4f 4b 20 |: A CLOSER LOOK | 00002eb0 41 54 20 50 41 43 4b 45 54 53 0d 0a 0d 0a 0d 0a |AT PACKETS......| 00002ec0 20 20 54 68 69 73 20 61 70 70 65 6e 64 69 78 20 | This appendix | 00002ed0 68 61 73 20 62 65 65 6e 20 69 6e 63 6c 75 64 65 |has been include| 00002ee0 64 20 20 69 6e 20 6f 72 64 65 72 20 74 6f 20 73 |d in order to s| 00002ef0 68 6f 77 20 77 68 61 74 20 70 61 63 6b 65 74 73 |how what packets| 00002f00 20 61 63 74 75 61 6c 6c 79 20 6c 6f 6f 6b 0d 0a | actually look..| 00002f10 20 20 6c 69 6b 65 2c 20 61 6e 64 20 74 6f 20 6f | like, and to o| 00002f20 66 66 65 72 20 73 6f 6d 65 20 73 6f 72 74 20 6f |ffer some sort o| 00002f30 66 20 73 74 61 72 74 69 6e 67 20 20 70 6f 69 6e |f starting poin| 00002f40 74 20 66 6f 72 20 64 65 62 75 67 67 69 6e 67 2e |t for debugging.| 00002f50 20 20 4d 6f 73 74 20 4b 45 52 4d 49 54 73 0d 0a | Most KERMITs..| 00002f60 20 20 6f 66 66 65 72 20 20 73 6f 6d 65 20 20 73 | offer some s| 00002f70 6f 72 74 20 6f 66 20 64 65 62 75 67 20 66 61 63 |ort of debug fac| 00002f80 69 6c 69 74 79 2c 20 74 68 65 20 6f 75 74 70 75 |ility, the outpu| 00002f90 74 20 66 72 6f 6d 20 20 77 68 69 63 68 20 20 77 |t from which w| 00002fa0 69 6c 6c 20 20 62 65 20 20 69 6e 20 20 61 0d 0a |ill be in a..| 00002fb0 20 20 73 69 6d 69 6c 61 72 20 66 6f 72 6d 20 74 | similar form t| 00002fc0 6f 20 20 74 68 65 20 20 65 78 61 6d 70 6c 65 20 |o the example | 00002fd0 20 73 68 6f 77 6e 20 20 62 65 6c 6f 77 2e 20 20 | shown below. | 00002fe0 52 65 66 65 72 65 6e 63 65 20 20 31 20 20 77 69 |Reference 1 wi| 00002ff0 6c 6c 20 67 69 76 65 20 61 20 6d 6f 72 65 0d 0a |ll give a more..| 00003000 20 20 64 65 74 61 69 6c 65 64 20 64 65 73 63 72 | detailed descr| 00003010 69 70 74 69 6f 6e 20 6f 66 20 74 68 65 20 73 74 |iption of the st| 00003020 72 75 63 74 75 72 65 20 6f 66 20 61 20 70 61 63 |ructure of a pac| 00003030 6b 65 74 20 74 68 61 6e 20 77 69 6c 6c 20 62 65 |ket than will be| 00003040 20 67 69 76 65 6e 20 68 65 72 65 2e 0d 0a 0d 0a | given here.....| 00003050 20 20 54 68 65 20 65 78 61 6d 70 6c 65 20 75 73 | The example us| 00003060 65 64 20 68 65 72 65 20 77 61 73 20 20 63 61 72 |ed here was car| 00003070 72 69 65 64 20 20 6f 75 74 20 20 62 65 74 77 65 |ried out betwe| 00003080 65 6e 20 20 61 20 6d 69 6e 69 20 61 6e 64 20 61 |en a mini and a| 00003090 20 6d 69 63 72 6f 20 73 79 73 74 65 6d 2e 0d 0a | micro system...| 000030a0 20 20 54 68 65 20 20 6d 69 6e 69 20 4b 45 52 4d | The mini KERM| 000030b0 49 54 20 77 61 73 20 20 70 75 74 20 20 69 6e 74 |IT was put int| 000030c0 6f 20 73 65 72 76 65 72 20 6d 6f 64 65 20 61 6e |o server mode an| 000030d0 64 2c 20 61 66 74 65 72 20 65 73 63 61 70 69 6e |d, after escapin| 000030e0 67 20 20 62 61 63 6b 20 74 6f 20 74 68 65 0d 0a |g back to the..| 000030f0 20 20 6d 69 63 72 6f 2c 20 74 68 65 20 66 69 6c | micro, the fil| 00003100 65 20 74 72 61 6e 73 66 65 72 20 77 61 73 20 69 |e transfer was i| 00003110 6e 69 74 69 61 74 65 64 20 62 79 20 74 68 65 20 |nitiated by the | 00003120 63 6f 6d 6d 61 6e 64 2c 0d 0a 0d 0a 20 20 20 20 |command,.... | 00003130 20 20 20 20 20 47 45 54 20 4b 45 52 4d 54 45 53 | GET KERMTES| 00003140 54 31 0d 0a 0d 0a 20 20 54 68 69 73 20 63 6f 6d |T1.... This com| 00003150 6d 61 6e 64 20 69 73 20 61 20 72 65 71 75 65 73 |mand is a reques| 00003160 74 20 74 6f 20 74 68 65 20 6d 69 6e 69 20 4b 45 |t to the mini KE| 00003170 52 4d 49 54 20 74 6f 20 73 65 6e 64 20 74 68 65 |RMIT to send the| 00003180 20 66 69 6c 65 20 4b 45 52 4d 54 45 53 54 31 2e | file KERMTEST1.| 00003190 0d 0a 0d 0a 20 20 54 68 65 20 70 61 63 6b 65 74 |.... The packet| 000031a0 73 20 77 65 72 65 20 72 65 63 6f 72 64 65 64 20 |s were recorded | 000031b0 64 75 72 69 6e 67 20 20 74 68 65 20 20 74 72 61 |during the tra| 000031c0 6e 73 66 65 72 20 20 62 79 20 20 74 68 65 20 6d |nsfer by the m| 000031d0 69 63 72 6f 20 4b 45 52 4d 49 54 20 20 64 65 62 |icro KERMIT deb| 000031e0 75 67 0d 0a 20 20 66 61 63 69 6c 69 74 79 2c 20 |ug.. facility, | 000031f0 20 77 68 69 63 68 20 20 6f 75 74 70 75 74 73 20 | which outputs | 00003200 74 68 65 20 63 6f 6e 74 65 6e 74 73 20 6f 66 20 |the contents of | 00003210 61 6c 6c 20 70 61 63 6b 65 74 73 2c 20 73 65 6e |all packets, sen| 00003220 74 20 61 6e 64 20 72 65 63 65 69 76 65 64 2c 20 |t and received, | 00003230 74 6f 0d 0a 20 20 74 68 65 20 70 72 69 6e 74 65 |to.. the printe| 00003240 72 2e 20 45 61 63 68 20 70 61 63 6b 65 74 20 69 |r. Each packet i| 00003250 73 20 70 72 65 66 69 78 65 64 20 77 69 74 68 20 |s prefixed with | 00003260 65 69 74 68 65 72 20 54 58 3a 20 6f 72 20 52 58 |either TX: or RX| 00003270 3a 20 77 68 65 6e 20 73 65 6e 74 20 74 6f 20 74 |: when sent to t| 00003280 68 65 0d 0a 20 20 70 72 69 6e 74 65 72 20 74 6f |he.. printer to| 00003290 20 69 6e 64 69 63 61 74 65 20 77 68 65 74 68 65 | indicate whethe| 000032a0 72 20 74 68 65 20 70 61 63 6b 65 74 20 69 73 20 |r the packet is | 000032b0 62 65 69 6e 67 20 74 72 61 6e 73 6d 69 74 74 65 |being transmitte| 000032c0 64 20 6f 72 20 72 65 63 65 69 76 65 64 2e 0d 0a |d or received...| 000032d0 0d 0a 20 20 54 68 65 20 70 61 63 6b 65 74 73 20 |.. The packets | 000032e0 73 65 6e 74 20 77 65 72 65 20 61 73 20 66 6f 6c |sent were as fol| 000032f0 6c 6f 77 73 3a 0d 0a 0d 0a 20 20 28 61 29 20 20 |lows:.... (a) | 00003300 20 20 54 58 3a 2b 20 49 7e 3e 20 40 2d 60 26 31 | TX:+ I~> @-`&1| 00003310 38 3c 4f 44 3e 0d 0a 20 20 28 62 29 20 20 20 20 |8<OD>.. (b) | 00003320 52 58 3a 2c 20 59 6e 25 20 40 2d 60 26 31 7e 5f |RX:, Yn% @-`&1~_| 00003330 3c 4f 44 3e 0d 0a 0d 0a 20 20 28 63 29 20 20 20 |<OD>.... (c) | 00003340 20 54 58 3a 2c 20 52 4b 45 52 4d 54 45 53 54 31 | TX:, RKERMTEST1| 00003350 5b 3c 4f 44 3e 0d 0a 20 20 28 64 29 20 20 20 20 |[<OD>.. (d) | 00003360 52 58 3a 2c 20 53 6e 25 20 40 2d 60 26 31 7e 59 |RX:, Sn% @-`&1~Y| 00003370 3c 4f 44 3e 0d 0a 20 20 28 65 29 20 20 20 20 54 |<OD>.. (e) T| 00003380 58 3a 2b 20 59 7e 3e 20 40 2d 60 26 31 48 3c 4f |X:+ Y~> @-`&1H<O| 00003390 44 3e 0d 0a 0d 0a 20 20 28 66 29 20 20 20 20 52 |D>.... (f) R| 000033a0 58 3a 2b 21 46 4b 45 52 4d 54 45 53 54 21 3c 4f |X:+!FKERMTEST!<O| 000033b0 44 3e 0d 0a 20 20 28 67 29 20 20 20 20 54 58 3a |D>.. (g) TX:| 000033c0 60 21 59 3f 3c 4f 44 3e 0d 0a 0d 0a 20 20 28 68 |`!Y?<OD>.... (h| 000033d0 29 20 20 20 20 52 58 3a 7a 22 44 74 68 69 73 20 |) RX:z"Dthis | 000033e0 69 73 20 61 20 74 65 73 74 20 66 69 6c 65 20 74 |is a test file t| 000033f0 6f 20 73 68 6f 77 60 4d 60 4a 77 68 61 74 20 70 |o show`M`Jwhat p| 00003400 61 63 6b 65 74 73 20 6c 6f 6f 6b 20 6c 69 6b 65 |ackets look like| 00003410 20 77 68 65 6e 60 4d 60 4a 0d 0a 20 20 20 20 20 | when`M`J.. | 00003420 20 20 20 20 64 61 74 61 20 69 73 20 62 65 69 6e | data is bein| 00003430 67 20 74 72 61 6e 73 6d 69 74 74 65 64 28 3c 4f |g transmitted(<O| 00003440 44 3e 0d 0a 20 20 28 69 29 20 20 20 20 54 58 3a |D>.. (i) TX:| 00003450 60 22 59 40 3c 4f 44 3e 0d 0a 0d 0a 20 20 28 6a |`"Y@<OD>.... (j| 00003460 29 20 20 20 20 52 58 3a 36 60 44 20 62 79 20 60 |) RX:6`D by `| 00003470 4d 60 4a 4b 45 52 4d 49 54 2e 60 4d 60 4a 4d 3c |M`JKERMIT.`M`JM<| 00003480 4f 44 3e 0d 0a 20 20 28 6b 29 20 20 20 20 54 58 |OD>.. (k) TX| 00003490 3a 60 60 59 41 3c 4f 44 3e 0d 0a 0d 0a 20 20 28 |:``YA<OD>.... (| 000034a0 6c 29 20 20 20 20 52 58 3a 60 24 5a 43 3c 4f 44 |l) RX:`$ZC<OD| 000034b0 3e 0d 0a 20 20 28 6d 29 20 20 20 20 54 58 3a 60 |>.. (m) TX:`| 000034c0 24 59 42 3c 4f 44 3e 0d 0a 0d 0a 20 20 28 6e 29 |$YB<OD>.... (n)| 000034d0 20 20 20 20 52 58 3a 60 25 42 2c 3c 4f 44 3e 0d | RX:`%B,<OD>.| 000034e0 0a 20 20 28 6f 29 20 20 20 20 54 58 3a 60 25 59 |. (o) TX:`%Y| 000034f0 43 3c 4f 44 3e 0d 0a 0d 0a 20 20 28 70 29 20 20 |C<OD>.... (p) | 00003500 20 20 54 58 3a 24 20 47 46 34 3c 4f 44 3e 0d 0a | TX:$ GF4<OD>..| 00003510 20 20 28 71 29 20 20 20 20 52 58 3a 60 20 59 3e | (q) RX:` Y>| 00003520 3c 4f 44 3e 0d 0a 0d 0a 0d 0a 0d 0a 20 20 54 68 |<OD>........ Th| 00003530 65 20 66 69 72 73 74 20 74 68 72 65 65 20 63 68 |e first three ch| 00003540 61 72 61 63 74 65 72 73 20 6f 66 20 20 65 61 63 |aracters of eac| 00003550 68 20 20 70 61 63 6b 65 74 20 20 6d 61 6b 65 20 |h packet make | 00003560 75 70 20 74 68 65 20 68 65 61 64 65 72 20 61 6e |up the header an| 00003570 64 20 69 6e 64 69 63 61 74 65 0d 0a 20 20 74 68 |d indicate.. th| 00003580 65 20 73 69 7a 65 20 6f 66 20 74 68 65 20 70 61 |e size of the pa| 00003590 63 6b 65 74 2c 20 74 68 65 20 70 61 63 6b 65 74 |cket, the packet| 000035a0 20 6e 75 6d 62 65 72 2c 20 20 61 6e 64 20 20 74 | number, and t| 000035b0 68 65 20 20 74 79 70 65 20 20 6f 66 20 20 74 68 |he type of th| 000035c0 65 20 20 70 61 63 6b 65 74 2c 0d 0a 20 20 72 65 |e packet,.. re| 000035d0 73 70 65 63 74 69 76 65 6c 79 2e 20 20 54 68 65 |spectively. The| 000035e0 20 20 3c 4f 44 3e 20 20 61 74 20 20 74 68 65 20 | <OD> at the | 000035f0 20 65 6e 64 20 20 6f 66 20 20 65 61 63 68 20 70 | end of each p| 00003600 61 63 6b 65 74 20 69 73 20 74 68 65 20 65 6e 64 |acket is the end| 00003610 2d 6f 66 2d 70 61 63 6b 65 74 0d 0a 20 20 69 6e |-of-packet.. in| 00003620 64 69 63 61 74 6f 72 20 28 69 6e 20 74 68 69 73 |dicator (in this| 00003630 20 63 61 73 65 20 61 20 63 61 72 72 69 61 67 65 | case a carriage| 00003640 20 72 65 74 75 72 6e 29 2e 20 54 68 65 20 63 68 | return). The ch| 00003650 61 72 61 63 74 65 72 20 69 6d 6d 65 64 69 61 74 |aracter immediat| 00003660 65 6c 79 20 62 65 66 6f 72 65 0d 0a 20 20 74 68 |ely before.. th| 00003670 65 20 20 3c 4f 44 3e 20 20 69 73 20 20 61 20 20 |e <OD> is a | 00003680 63 68 65 63 6b 73 75 6d 20 63 68 61 72 61 63 74 |checksum charact| 00003690 65 72 2e 20 20 28 54 68 65 20 61 6c 67 6f 72 69 |er. (The algori| 000036a0 74 68 6d 20 20 75 73 65 64 20 20 66 6f 72 20 20 |thm used for | 000036b0 63 6f 64 69 6e 67 20 74 68 65 0d 0a 20 20 63 68 |coding the.. ch| 000036c0 65 63 6b 73 75 6d 20 63 61 6e 20 62 65 20 66 6f |ecksum can be fo| 000036d0 75 6e 64 20 69 6e 20 72 65 66 65 72 65 6e 63 65 |und in reference| 000036e0 20 31 2e 29 0d 0a 0d 0a 0d 0a 20 20 41 6e 20 49 | 1.)...... An I| 000036f0 6e 74 72 6f 64 75 63 74 69 6f 6e 20 74 6f 20 4b |ntroduction to K| 00003700 65 72 6d 69 74 20 20 20 20 20 20 20 20 20 20 20 |ermit | 00003710 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | * 00003730 20 20 50 61 67 65 20 35 0d 0a 0d 0a 0d 0a 0d 0a | Page 5........| 00003740 0d 0a 0d 0a 20 20 54 68 65 20 63 68 61 72 61 63 |.... The charac| 00003750 74 65 72 73 20 62 65 74 77 65 65 6e 20 74 68 65 |ters between the| 00003760 20 68 65 61 64 65 72 20 20 61 6e 64 20 20 74 68 | header and th| 00003770 65 20 20 63 68 65 63 6b 73 75 6d 20 20 63 68 61 |e checksum cha| 00003780 72 61 63 74 65 72 20 6d 61 6b 65 20 75 70 20 74 |racter make up t| 00003790 68 65 0d 0a 20 20 64 61 74 61 20 66 69 65 6c 64 |he.. data field| 000037a0 2e 0d 0a 0d 0a 20 20 54 68 65 20 70 61 63 6b 65 |..... The packe| 000037b0 74 20 74 79 70 65 73 20 75 73 65 64 20 69 6e 20 |t types used in | 000037c0 74 68 69 73 20 74 72 61 6e 73 66 65 72 2c 20 20 |this transfer, | 000037d0 69 6e 64 69 63 61 74 65 64 20 62 79 20 74 68 65 |indicated by the| 000037e0 20 74 68 69 72 64 20 63 68 61 72 61 63 74 65 72 | third character| 000037f0 20 6f 66 0d 0a 20 20 74 68 65 20 70 61 63 6b 65 | of.. the packe| 00003800 74 2c 20 77 65 72 65 20 61 73 20 66 6f 6c 6c 6f |t, were as follo| 00003810 77 73 3a 0d 0a 0d 0a 20 20 20 20 20 20 20 20 20 |ws:.... | 00003820 49 20 20 20 69 6e 69 74 2d 69 6e 66 6f 2e 0d 0a |I init-info...| 00003830 20 20 20 20 20 20 20 20 20 59 20 20 20 61 63 6b | Y ack| 00003840 6e 6f 77 6c 65 64 67 6d 65 6e 74 0d 0a 20 20 20 |nowledgment.. | 00003850 20 20 20 20 20 20 52 20 20 20 52 20 74 79 70 65 | R R type| 00003860 0d 0a 20 20 20 20 20 20 20 20 20 53 20 20 20 73 |.. S s| 00003870 65 6e 64 2d 69 6e 69 74 2e 0d 0a 20 20 20 20 20 |end-init... | 00003880 20 20 20 20 46 20 20 20 66 69 6c 65 20 68 65 61 | F file hea| 00003890 64 65 72 0d 0a 20 20 20 20 20 20 20 20 20 44 20 |der.. D | 000038a0 20 20 64 61 74 61 0d 0a 20 20 20 20 20 20 20 20 | data.. | 000038b0 20 5a 20 20 20 65 6e 64 2d 6f 66 2d 66 69 6c 65 | Z end-of-file| 000038c0 0d 0a 20 20 20 20 20 20 20 20 20 42 20 20 20 65 |.. B e| 000038d0 6e 64 2d 6f 66 2d 74 72 61 6e 73 66 65 72 0d 0a |nd-of-transfer..| 000038e0 20 20 20 20 20 20 20 20 20 47 20 20 20 4b 45 52 | G KER| 000038f0 4d 49 54 20 63 6f 6d 6d 61 6e 64 0d 0a 0d 0a 0d |MIT command.....| 00003900 0a 20 20 50 61 63 6b 65 74 20 28 61 29 2c 20 61 |. Packet (a), a| 00003910 6e 20 69 6e 69 74 2d 69 6e 66 6f 20 70 61 63 6b |n init-info pack| 00003920 65 74 2c 20 20 77 61 73 20 73 65 6e 74 20 62 79 |et, was sent by| 00003930 20 74 68 65 20 6d 69 63 72 6f 20 70 72 69 6f 72 | the micro prior| 00003940 20 74 6f 20 73 65 6e 64 69 6e 67 20 74 68 65 0d | to sending the.| 00003950 0a 20 20 72 65 71 75 65 73 74 20 66 6f 72 20 61 |. request for a| 00003960 20 66 69 6c 65 2e 20 20 54 68 65 20 6d 69 6e 69 | file. The mini| 00003970 20 61 63 6b 6e 6f 77 6c 65 64 67 65 64 20 74 68 | acknowledged th| 00003980 69 73 20 70 61 63 6b 65 74 20 69 6e 20 74 68 65 |is packet in the| 00003990 20 75 73 75 61 6c 20 77 61 79 2e 20 54 68 65 0d | usual way. The.| 000039a0 0a 20 20 65 78 63 68 61 6e 67 65 20 6f 66 20 74 |. exchange of t| 000039b0 68 65 73 65 20 74 77 6f 20 70 61 63 6b 65 74 73 |hese two packets| 000039c0 20 69 73 20 6e 65 63 65 73 73 61 72 79 20 74 6f | is necessary to| 000039d0 20 65 73 74 61 62 6c 69 73 68 20 77 68 61 74 20 | establish what | 000039e0 66 61 63 69 6c 69 74 69 65 73 20 65 61 63 68 0d |facilities each.| 000039f0 0a 20 20 4b 45 52 4d 49 54 20 68 61 73 2e 0d 0a |. KERMIT has...| 00003a00 0d 0a 20 20 50 61 63 6b 65 74 20 28 63 29 20 77 |.. Packet (c) w| 00003a10 61 73 20 74 68 65 20 72 65 71 75 65 73 74 20 66 |as the request f| 00003a20 72 6f 6d 20 74 68 65 20 6d 69 63 72 6f 20 74 6f |rom the micro to| 00003a30 20 74 68 65 20 6d 69 6e 69 20 66 6f 72 20 74 68 | the mini for th| 00003a40 65 20 66 69 6c 65 20 4b 45 52 4d 54 45 53 54 31 |e file KERMTEST1| 00003a50 0d 0a 20 20 61 6e 64 20 69 73 20 61 6e 20 52 20 |.. and is an R | 00003a60 74 79 70 65 20 70 61 63 6b 65 74 2e 20 20 54 68 |type packet. Th| 00003a70 65 20 6d 69 6e 69 20 20 69 6e 69 74 69 61 74 65 |e mini initiate| 00003a80 64 20 20 74 68 65 20 66 69 6c 65 20 20 74 72 61 |d the file tra| 00003a90 6e 73 66 65 72 20 62 79 20 73 65 6e 64 69 6e 67 |nsfer by sending| 00003aa0 0d 0a 20 20 61 20 73 65 6e 64 2d 69 6e 69 74 20 |.. a send-init | 00003ab0 70 61 63 6b 65 74 2c 20 70 61 63 6b 65 74 20 28 |packet, packet (| 00003ac0 64 29 2c 20 77 68 69 63 68 20 74 68 65 20 6d 69 |d), which the mi| 00003ad0 63 72 6f 20 69 6e 20 74 75 72 6e 20 61 63 6b 6e |cro in turn ackn| 00003ae0 6f 77 6c 65 64 67 65 64 2e 20 28 4e 6f 74 65 3a |owledged. (Note:| 00003af0 0d 0a 20 20 70 61 63 6b 65 74 73 20 28 61 29 20 |.. packets (a) | 00003b00 61 6e 64 20 28 62 29 20 61 72 65 20 76 65 72 79 |and (b) are very| 00003b10 20 73 69 6d 69 6c 61 72 20 20 74 6f 20 70 61 63 | similar to pac| 00003b20 6b 65 74 73 20 28 64 29 20 61 6e 64 20 28 65 29 |kets (d) and (e)| 00003b30 2e 20 20 49 6e 20 62 6f 74 68 20 63 61 73 65 73 |. In both cases| 00003b40 0d 0a 20 20 69 6e 66 6f 72 6d 61 74 69 6f 6e 20 |.. information | 00003b50 77 61 73 20 62 65 69 6e 67 20 65 78 63 68 61 6e |was being exchan| 00003b60 67 65 64 20 61 62 6f 75 74 20 74 68 65 20 66 61 |ged about the fa| 00003b70 63 69 6c 69 74 69 65 73 20 74 68 61 74 20 65 61 |cilities that ea| 00003b80 63 68 20 4b 45 52 4d 49 54 20 68 61 64 20 74 6f |ch KERMIT had to| 00003b90 0d 0a 20 20 6f 66 66 65 72 2e 20 20 53 65 65 20 |.. offer. See | 00003ba0 72 65 66 65 72 65 6e 63 65 20 31 20 66 6f 72 20 |reference 1 for | 00003bb0 6d 6f 72 65 20 64 65 74 61 69 6c 73 2e 29 0d 0a |more details.)..| 00003bc0 0d 0a 20 20 46 72 6f 6d 20 70 61 63 6b 65 74 20 |.. From packet | 00003bd0 28 66 29 20 74 6f 20 70 61 63 6b 65 74 20 20 28 |(f) to packet (| 00003be0 6f 29 20 74 68 65 20 70 61 74 74 65 72 6e 20 6f |o) the pattern o| 00003bf0 66 20 27 72 65 63 65 69 76 65 20 64 61 74 61 20 |f 'receive data | 00003c00 74 68 65 6e 20 61 63 6b 6e 6f 77 6c 65 64 67 65 |then acknowledge| 00003c10 0d 0a 20 20 69 74 27 20 20 77 61 73 20 72 65 70 |.. it' was rep| 00003c20 65 61 74 65 64 20 75 6e 74 69 6c 20 74 68 65 20 |eated until the | 00003c30 74 72 61 6e 73 66 65 72 20 20 77 61 73 20 20 63 |transfer was c| 00003c40 6f 6d 70 6c 65 74 65 2e 20 20 50 61 63 6b 65 74 |omplete. Packet| 00003c50 73 20 20 28 68 29 20 20 61 6e 64 20 20 28 6a 29 |s (h) and (j)| 00003c60 0d 0a 20 20 63 6f 6e 74 61 69 6e 20 74 68 65 20 |.. contain the | 00003c70 61 63 74 75 61 6c 20 63 6f 6e 74 65 6e 74 73 20 |actual contents | 00003c80 6f 66 20 74 68 65 20 66 69 6c 65 20 62 65 69 6e |of the file bein| 00003c90 67 20 74 72 61 6e 73 66 65 72 72 65 64 2e 20 54 |g transferred. T| 00003ca0 68 65 20 27 23 4d 23 4a 27 20 73 74 72 69 6e 67 |he '#M#J' string| 00003cb0 0d 0a 20 20 69 6e 20 74 68 65 20 20 64 61 74 61 |.. in the data| 00003cc0 20 20 66 69 65 6c 64 20 6f 66 20 74 68 65 73 65 | field of these| 00003cd0 20 70 61 63 6b 65 74 73 20 69 6e 64 69 63 61 74 | packets indicat| 00003ce0 65 20 74 68 65 20 63 61 72 72 69 61 67 65 20 72 |e the carriage r| 00003cf0 65 74 75 72 6e 73 20 20 61 6e 64 20 6c 69 6e 65 |eturns and line| 00003d00 0d 0a 20 20 66 65 65 64 73 20 69 6e 20 74 68 65 |.. feeds in the| 00003d10 20 66 69 6c 65 2e 20 20 54 68 65 20 20 72 65 61 | file. The rea| 00003d20 73 6f 6e 20 20 66 6f 72 20 20 74 68 69 73 20 72 |son for this r| 00003d30 65 70 72 65 73 65 6e 74 61 74 69 6f 6e 20 69 73 |epresentation is| 00003d40 20 74 68 61 74 20 74 68 65 20 4b 45 52 4d 49 54 | that the KERMIT| 00003d50 0d 0a 20 20 70 72 6f 74 6f 63 6f 6c 20 20 6f 6e |.. protocol on| 00003d60 6c 79 20 20 61 6c 6c 6f 77 73 20 20 70 72 69 6e |ly allows prin| 00003d70 74 61 62 6c 65 20 20 63 68 61 72 61 63 74 65 72 |table character| 00003d80 73 20 74 6f 20 62 65 20 75 73 65 64 20 20 69 6e |s to be used in| 00003d90 20 20 70 61 63 6b 65 74 73 20 20 28 69 2e 65 2e | packets (i.e.| 00003da0 0d 0a 20 20 63 68 61 72 61 63 74 65 72 73 20 77 |.. characters w| 00003db0 69 74 68 20 41 53 43 49 49 20 76 61 6c 75 65 73 |ith ASCII values| 00003dc0 20 62 65 74 77 65 65 6e 20 33 32 20 61 6e 64 20 | between 32 and | 00003dd0 31 32 36 20 69 6e 63 6c 75 73 69 76 65 29 2e 0d |126 inclusive)..| 00003de0 0a 0d 0a 20 20 50 72 69 6f 72 20 74 6f 20 74 68 |... Prior to th| 00003df0 65 20 73 74 61 72 74 20 6f 66 20 20 74 68 65 20 |e start of the | 00003e00 20 66 69 6c 65 20 20 74 72 61 6e 73 66 65 72 20 | file transfer | 00003e10 20 28 70 61 63 6b 65 74 73 20 28 61 29 20 74 6f | (packets (a) to| 00003e20 20 28 63 29 29 2c 20 74 68 65 20 70 61 63 6b 65 | (c)), the packe| 00003e30 74 0d 0a 20 20 6e 75 6d 62 65 72 20 20 72 65 6d |t.. number rem| 00003e40 61 69 6e 65 64 20 20 61 74 20 20 30 20 20 28 72 |ained at 0 (r| 00003e50 65 70 72 65 73 65 6e 74 65 64 20 62 79 20 61 20 |epresented by a | 00003e60 73 70 61 63 65 29 2e 20 20 41 66 74 65 72 20 74 |space). After t| 00003e70 68 69 73 20 68 6f 77 65 76 65 72 2c 20 20 74 68 |his however, th| 00003e80 65 0d 0a 20 20 70 61 63 6b 65 74 20 20 6e 75 6d |e.. packet num| 00003e90 62 65 72 20 20 77 61 73 20 20 69 6e 63 72 65 6d |ber was increm| 00003ea0 65 6e 74 65 64 20 20 62 79 20 31 20 66 6f 72 20 |ented by 1 for | 00003eb0 65 61 63 68 20 70 61 63 6b 65 74 20 74 68 61 74 |each packet that| 00003ec0 20 77 61 73 20 73 75 63 63 65 73 73 66 75 6c 6c | was successfull| 00003ed0 79 0d 0a 20 20 74 72 61 6e 73 66 65 72 72 65 64 |y.. transferred| 00003ee0 2e 20 20 54 68 65 20 61 63 6b 6e 6f 77 6c 65 64 |. The acknowled| 00003ef0 67 6d 65 6e 74 20 70 61 63 6b 65 74 73 20 66 72 |gment packets fr| 00003f00 6f 6d 20 74 68 65 20 6d 69 63 72 6f 20 68 61 76 |om the micro hav| 00003f10 65 20 74 68 65 20 73 61 6d 65 20 70 61 63 6b 65 |e the same packe| 00003f20 74 0d 0a 20 20 6e 75 6d 62 65 72 20 61 73 20 74 |t.. number as t| 00003f30 68 65 20 70 61 63 6b 65 74 20 74 68 61 74 20 77 |he packet that w| 00003f40 61 73 20 62 65 69 6e 67 20 61 63 6b 6e 6f 77 6c |as being acknowl| 00003f50 65 64 67 65 64 2e 20 54 68 65 20 70 61 63 6b 65 |edged. The packe| 00003f60 74 20 6e 75 6d 62 65 72 20 69 73 20 63 6f 64 65 |t number is code| 00003f70 64 0d 0a 20 20 69 6e 74 6f 20 61 20 73 69 6e 67 |d.. into a sing| 00003f80 6c 65 20 63 68 61 72 61 63 74 65 72 2c 20 20 62 |le character, b| 00003f90 61 73 65 64 20 20 6f 6e 20 41 53 43 49 49 20 76 |ased on ASCII v| 00003fa0 61 6c 75 65 73 2c 20 61 63 63 6f 72 64 69 6e 67 |alues, according| 00003fb0 20 74 6f 20 74 68 65 20 61 6c 67 6f 72 69 74 68 | to the algorith| 00003fc0 6d 0d 0a 20 20 73 65 74 20 64 6f 77 6e 20 69 6e |m.. set down in| 00003fd0 20 72 65 66 65 72 65 6e 63 65 20 31 2e 0d 0a 0d | reference 1....| 00003fe0 0a 0d 0a 20 20 50 61 63 6b 65 74 73 20 28 6c 29 |... Packets (l)| 00003ff0 20 61 6e 64 20 28 6e 29 20 77 65 72 65 20 73 65 | and (n) were se| 00004000 6e 74 20 74 6f 20 73 69 67 6e 69 66 79 20 74 68 |nt to signify th| 00004010 65 20 65 6e 64 2d 6f 66 2d 66 69 6c 65 20 61 6e |e end-of-file an| 00004020 64 20 65 6e 64 2d 6f 66 2d 74 72 61 6e 73 66 65 |d end-of-transfe| 00004030 72 0d 0a 20 20 72 65 73 70 65 63 74 69 76 65 6c |r.. respectivel| 00004040 79 20 61 6e 64 20 63 6f 6e 74 61 69 6e 20 6e 6f |y and contain no| 00004050 20 64 61 74 61 2e 0d 0a 0d 0a 20 20 50 61 63 6b | data..... Pack| 00004060 65 74 20 28 70 29 20 77 61 73 20 6e 6f 74 20 70 |et (p) was not p| 00004070 61 72 74 20 20 6f 66 20 20 74 68 65 20 20 66 69 |art of the fi| 00004080 6c 65 20 20 74 72 61 6e 73 66 65 72 2c 20 20 62 |le transfer, b| 00004090 75 74 20 20 77 61 73 20 61 20 4b 45 52 4d 49 54 |ut was a KERMIT| 000040a0 20 63 6f 6d 6d 61 6e 64 0d 0a 20 20 70 61 63 6b | command.. pack| 000040b0 65 74 2c 20 20 77 68 69 63 68 20 20 72 65 73 75 |et, which resu| 000040c0 6c 74 65 64 20 20 66 72 6f 6d 20 74 68 65 20 46 |lted from the F| 000040d0 49 4e 49 53 48 20 63 6f 6d 6d 61 6e 64 20 67 69 |INISH command gi| 000040e0 76 65 6e 20 74 6f 20 74 68 65 20 6d 69 63 72 6f |ven to the micro| 000040f0 20 4b 45 52 4d 49 54 2e 0d 0a 20 20 54 68 65 20 | KERMIT... The | 00004100 64 61 74 61 20 66 69 65 6c 64 20 6f 66 20 20 74 |data field of t| 00004110 68 65 20 20 4b 45 52 4d 49 54 20 20 63 6f 6d 6d |he KERMIT comm| 00004120 61 6e 64 20 20 70 61 63 6b 65 74 20 20 63 6f 6e |and packet con| 00004130 74 61 69 6e 65 64 20 20 61 20 20 73 69 6e 67 6c |tained a singl| 00004140 65 20 6c 65 74 74 65 72 0d 0a 20 20 63 6f 6d 6d |e letter.. comm| 00004150 61 6e 64 2c 20 69 6e 20 74 68 69 73 20 63 61 73 |and, in this cas| 00004160 65 20 61 6e 20 46 2c 20 69 6e 64 69 63 61 74 69 |e an F, indicati| 00004170 6e 67 20 74 6f 20 74 68 65 20 6d 69 6e 69 20 4b |ng to the mini K| 00004180 45 52 4d 49 54 20 20 74 68 61 74 20 20 69 74 20 |ERMIT that it | 00004190 20 77 61 73 20 20 74 6f 0d 0a 20 20 73 68 75 74 | was to.. shut| 000041a0 20 20 64 6f 77 6e 20 20 69 74 73 20 20 73 65 72 | down its ser| 000041b0 76 65 72 2e 20 20 20 50 61 63 6b 65 74 20 28 71 |ver. Packet (q| 000041c0 29 20 77 61 73 20 61 6e 20 61 63 6b 6e 6f 77 6c |) was an acknowl| 000041d0 65 64 67 6d 65 6e 74 20 74 6f 20 74 68 69 73 20 |edgment to this | 000041e0 63 6f 6d 6d 61 6e 64 2e 0d 0a 20 20 4e 6f 74 65 |command... Note| 000041f0 20 74 68 61 74 20 74 68 65 20 70 61 63 6b 65 74 | that the packet| 00004200 20 6e 75 6d 62 65 72 20 20 77 61 73 20 20 73 65 | number was se| 00004210 74 20 62 61 63 6b 20 74 6f 20 30 20 73 69 6e 63 |t back to 0 sinc| 00004220 65 20 74 68 65 73 65 20 74 77 6f 20 70 61 63 6b |e these two pack| 00004230 65 74 73 20 77 65 72 65 0d 0a 20 20 6e 6f 74 20 |ets were.. not | 00004240 70 61 72 74 20 6f 66 20 74 68 65 20 66 69 6c 65 |part of the file| 00004250 20 74 72 61 6e 73 66 65 72 2e 0d 0a 0d 0a 0d 0a | transfer.......| 00004260 0d 0a 0d 0a 20 20 41 6e 20 49 6e 74 72 6f 64 75 |.... An Introdu| 00004270 63 74 69 6f 6e 20 74 6f 20 4b 65 72 6d 69 74 20 |ction to Kermit | 00004280 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | * 000042a0 20 20 20 20 20 20 20 20 20 20 20 20 50 61 67 65 | Page| 000042b0 20 36 0d 0a 0d 0a 0d 0a 0d 0a 0d 0a 0d 0a 20 20 | 6............ | 000042c0 41 50 50 45 4e 44 49 58 20 42 20 3a 20 52 45 46 |APPENDIX B : REF| 000042d0 45 52 45 4e 43 45 53 0d 0a 0d 0a 0d 0a 20 20 5b |ERENCES...... [| 000042e0 31 5d 20 20 4b 45 52 4d 49 54 20 50 72 6f 74 6f |1] KERMIT Proto| 000042f0 63 6f 6c 20 4d 61 6e 75 61 6c 20 28 53 69 78 74 |col Manual (Sixt| 00004300 68 20 20 45 64 69 74 69 6f 6e 29 2e 20 20 46 72 |h Edition). Fr| 00004310 61 6e 6b 20 64 61 20 43 72 75 7a 2c 20 43 6f 6c |ank da Cruz, Col| 00004320 75 6d 62 69 61 0d 0a 20 20 20 20 20 20 20 55 6e |umbia.. Un| 00004330 69 76 65 72 73 69 74 79 20 43 65 6e 74 65 72 20 |iversity Center | 00004340 66 6f 72 20 43 6f 6d 70 75 74 69 6e 67 20 41 63 |for Computing Ac| 00004350 74 69 76 69 74 69 65 73 20 4e 65 77 20 59 6f 72 |tivities New Yor| 00004360 6b 2c 20 4e 2e 59 2e 20 31 30 30 32 37 2e 0d 0a |k, N.Y. 10027...| 00004370 0d 0a 20 20 20 20 20 20 20 54 68 65 20 73 61 6d |.. The sam| 00004380 65 20 69 6e 66 6f 72 6d 61 74 69 6f 6e 20 69 73 |e information is| 00004390 20 63 6f 76 65 72 65 64 20 69 6e 20 61 20 6d 6f | covered in a mo| 000043a0 72 65 20 69 6e 66 6f 72 6d 61 6c 20 77 61 79 2c |re informal way,| 000043b0 20 77 69 74 68 20 66 61 72 20 6d 6f 72 65 0d 0a | with far more..| 000043c0 20 20 20 20 20 20 20 69 6e 20 74 68 65 20 77 61 | in the wa| 000043d0 79 20 6f 66 20 65 78 70 6c 61 6e 61 74 69 6f 6e |y of explanation| 000043e0 20 61 6e 64 20 65 78 61 6d 70 6c 65 2c 20 69 6e | and example, in| 000043f0 0d 0a 0d 0a 20 20 20 20 20 20 20 22 4b 65 72 6d |.... "Kerm| 00004400 69 74 20 3a 20 41 20 46 69 6c 65 20 54 72 61 6e |it : A File Tran| 00004410 73 66 65 72 20 50 72 6f 74 6f 63 6f 6c 22 20 62 |sfer Protocol" b| 00004420 79 20 46 72 61 6e 6b 20 64 61 20 43 72 75 7a 20 |y Frank da Cruz | 00004430 28 70 75 62 2e 20 44 69 67 69 74 61 6c 20 50 72 |(pub. Digital Pr| 00004440 65 73 73 29 0d 0a 0d 0a 0d 0a 0d 0a 0d 0a 20 20 |ess).......... | 00004450 41 50 50 45 4e 44 49 58 20 43 20 3a 20 57 48 45 |APPENDIX C : WHE| 00004460 52 45 20 54 4f 20 47 45 54 20 4b 45 52 4d 49 54 |RE TO GET KERMIT| 00004470 0d 0a 0d 0a 0d 0a 20 20 4b 65 72 6d 69 74 20 70 |...... Kermit p| 00004480 72 6f 67 72 61 6d 73 20 61 72 65 20 61 76 61 69 |rograms are avai| 00004490 6c 61 62 6c 65 20 6f 6e 20 20 6d 61 6e 79 20 20 |lable on many | 000044a0 62 75 6c 6c 65 74 69 6e 20 62 6f 61 72 64 20 73 |bulletin board s| 000044b0 79 73 74 65 6d 73 20 61 6e 64 20 66 72 6f 6d 20 |ystems and from | 000044c0 75 73 65 72 0d 0a 20 20 67 72 6f 75 70 73 2e 20 |user.. groups. | 000044d0 20 54 68 65 72 65 20 61 72 65 20 61 20 66 65 77 | There are a few| 000044e0 20 63 65 6e 74 72 65 73 20 74 68 61 74 20 63 61 | centres that ca| 000044f0 6e 20 70 72 6f 76 69 64 65 20 61 6c 6c 20 6b 6e |n provide all kn| 00004500 6f 77 6e 20 69 6d 70 6c 65 6d 65 6e 74 61 74 69 |own implementati| 00004510 6f 6e 73 2c 0d 0a 20 20 61 73 20 66 6f 6c 6c 6f |ons,.. as follo| 00004520 77 73 3a 0d 0a 0d 0a 20 20 61 2e 20 57 6f 72 6c |ws:.... a. Worl| 00004530 64 2d 57 69 64 65 20 44 69 73 74 72 69 62 75 74 |d-Wide Distribut| 00004540 69 6f 6e 0d 0a 0d 0a 20 20 20 20 20 20 20 20 20 |ion.... | 00004550 20 20 20 20 20 20 20 20 4b 65 72 6d 69 74 20 44 | Kermit D| 00004560 69 73 74 72 69 62 75 74 69 6f 6e 0d 0a 20 20 20 |istribution.. | 00004570 20 20 20 20 20 20 20 20 20 20 20 20 20 20 43 6f | Co| 00004580 6c 75 6d 62 69 61 20 55 6e 69 76 65 72 73 69 74 |lumbia Universit| 00004590 79 20 43 65 6e 74 65 72 20 66 6f 72 20 43 6f 6d |y Center for Com| 000045a0 70 75 74 69 6e 67 20 41 63 74 69 76 69 74 69 65 |puting Activitie| 000045b0 73 0d 0a 20 20 20 20 20 20 20 20 20 20 20 20 20 |s.. | 000045c0 20 20 20 20 37 74 68 20 46 6c 6f 6f 72 0d 0a 20 | 7th Floor.. | 000045d0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | 000045e0 36 31 32 20 57 65 73 74 20 31 31 35 74 68 20 53 |612 West 115th S| 000045f0 74 72 65 65 74 0d 0a 20 20 20 20 20 20 20 20 20 |treet.. | 00004600 20 20 20 20 20 20 20 20 4e 65 77 20 59 6f 72 6b | New York| 00004610 0d 0a 20 20 20 20 20 20 20 20 20 20 20 20 20 20 |.. | 00004620 20 20 20 4e 59 20 31 30 30 32 35 0d 0a 20 20 20 | NY 10025.. | 00004630 20 20 20 20 20 20 20 20 20 20 20 20 20 20 55 6e | Un| 00004640 69 74 65 64 20 53 74 61 74 65 73 0d 0a 0d 0a 20 |ited States.... | 00004650 20 62 2e 20 44 69 73 74 72 69 62 75 74 69 6f 6e | b. Distribution| 00004660 20 69 6e 20 74 68 65 20 55 4b 20 61 6e 64 20 49 | in the UK and I| 00004670 72 65 6c 61 6e 64 20 6f 6e 6c 79 0d 0a 0d 0a 20 |reland only.... | 00004680 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | 00004690 4b 65 72 6d 69 74 20 44 69 73 74 72 69 62 75 74 |Kermit Distribut| 000046a0 69 6f 6e 0d 0a 20 20 20 20 20 20 20 20 20 20 20 |ion.. | 000046b0 20 20 20 20 20 20 44 65 70 61 72 74 6d 65 6e 74 | Department| 000046c0 20 6f 66 20 43 6f 6d 70 75 74 69 6e 67 0d 0a 20 | of Computing.. | 000046d0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | 000046e0 43 6f 6d 70 75 74 65 72 20 43 65 6e 74 72 65 0d |Computer Centre.| 000046f0 0a 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 |. | 00004700 20 20 4c 61 6e 63 61 73 74 65 72 20 55 6e 69 76 | Lancaster Univ| 00004710 65 72 73 69 74 79 0d 0a 20 20 20 20 20 20 20 20 |ersity.. | 00004720 20 20 20 20 20 20 20 20 20 4c 61 6e 63 61 73 74 | Lancast| 00004730 65 72 20 4c 41 31 20 34 59 57 0d 0a 20 20 20 20 |er LA1 4YW.. | 00004740 20 20 20 20 20 20 20 20 20 20 20 20 20 55 6e 69 | Uni| 00004750 74 65 64 20 4b 69 6e 67 64 6f 6d 0d 0a 0d 0a 0d |ted Kingdom.....| 00004760 0a 0d 0a 0d 0a 0d 0a 0d 0a 0d 0a 0d 0a 0d 0a 0d |................| * 00004780 0a 0d 0a 0d 0a 0d 0a 20 20 41 6e 20 49 6e 74 72 |....... An Intr| 00004790 6f 64 75 63 74 69 6f 6e 20 74 6f 20 4b 65 72 6d |oduction to Kerm| 000047a0 69 74 20 20 20 20 20 20 20 20 20 20 20 20 20 20 |it | 000047b0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | 000047c0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 50 | P| 000047d0 61 67 65 20 37 0d 0a 0d 0a 0d 0a 0d 0a 0d 0a |age 7..........| 000047df
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