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IETF RFC 216
Telnet Access to UCSB's On-Line System
Last modified on Thursday, January 7th, 2010
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Network Working Group J. White
Request for Comments: 216 UCSB Computer Research Lab
Categories: D.3, G.3 September 1971
NIC: 7546
Telnet Access To UCSB's Online System
Contents
I. Motivation .................................................1
II. Limitations ................................................2
III. System Documentation .......................................2
IV. System Access ..............................................3
V. Software Structure .........................................3
VI. Virtual OLS Keyboard .......................................4
VII. NETOLS Commands ...........................................10
A. HELP ...................................................10
B. PREFIX .................................................10
C. SHIFT and UNSHIFT ......................................10
D. FULLDUPLEX and HALFDUPLEX ..............................10
E. STATE ..................................................11
F. LOGOUT .................................................11
VIII. OLS Display ...............................................11
IX. Instructing User Telnet ...................................12
X. Examples ..................................................14
A. Logon ..................................................14
B. Newton-Raphson Square Root Approximation ...............15
C. Remote Job Entry .......................................16
Figures
Figure 1. OLS Keyboard .............................................2
Figure 2. Keys With One-for-One Mappings ...........................6
Figure 3. Keys Represented as Strings ..............................7
Figure 4. Characters With One-for-One Mappings ....................12
Figure 5. Characters Which Map Into Strings .......................13
I. Motivation
A teletype-compatible interface to UCSB's Online System (OLS) has
been implemented in accordance with the Telnet protocol adopted by
the NWG. This Server Telnet is responsive to connection requests
directed by User Telnet's to socket number 1, host address 3.
Although OLS is not a teletype system and although much of its power
as mathematical tool rests in its graphical display capabilities,
enough of the System survives the Telnet transformation to justify
such an implementation.
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RFC 216 Telnet Access To UCSB's On-Line System September 1971
II. Limitations
In this Telnet-style implementation of OLS, all curvilinear display
generated by the user on Levels II and III, Real and Complex, is
disregarded by the System and hence not returned to the user through
the Net. The same is true of the display of special, user-created
characters. Although special characters may be constructed and
stored, their display will be suppressed, both during the process of
construction and later when they are invoked from the Type level.
All other display generated by the System will be relayed to the user
intact, in some cases with stylistic transformation having first been
applied. For example, Greek characters are displayed as lower-case
a-z. All such transformations are described in detail in this
document. Finally, those elements of the System (the operators which
edit user programs are prime examples) which assume a fixed-screen
display device function abnormally in a Telnet environment. For such
a device, the System can "remember" the position on the screen of a
previously displayed segment of text and return to that position to,
for example, underscore it. But when the "screen" marches forward --
relentlessly -- through a continuous medium, as it does with Telnet's
virtual teletype, that kind of strategy fails. Hence, the
underscoring is not relocated, but rather appears on the current
line, beginning in the next available character frame.
OLS assumes, normally, that the user is equipped with the specially-
designed double keyboard depicted in Figure 1. Conventions are
defined in this document, which enable a Telnet user to simulate that
keyboard; in particular, a means is provided for designating keys on
the upper, or operator keyboard.
III. System Documentation
This document has three purposes:
Figure 1. OLS Keyboard. [Please view the PDF version of this RFC.]
(1) to describe the means by which a Telnet user simulates an OLS
keyboard,
(2) to describe the transformations applied to output generated by
the System, and
(3) to enumerate those aspects of the System, which are unique to or
behave differently for Network (Telnet) users.
In particular, this document is not a user's manual for OLS. Such a
manual is available and on file with the NIC. In addition, a copy
should exist at each Network site in its NIC collection; the user
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RFC 216 Telnet Access To UCSB's On-Line System September 1971
should consult his Station Agent. This document is titled "UCSB On-
Line System Manual" [NIC 5748]; its contents are current as of 1
January 71. A revision to the manual is currently in preparation and
will be distributed when available. In addition, tutorial manuals
for two of the subsystems available under OLS-MOLSF (Mathematically-
Oriented Language Single-Precision Floating-Point) and COL (Card
Oriented Language) -- will soon be made available. The latter has
already been published and is being transmitted to the NIC for
distribution, while the former is nearing completion.
Documentation of the third subsystem of OLS--NET-- has already been
distributed through the NIC as two RFC's: "Network On-Line Operators"
[21 April 71, RFC 121, NIC 5833] and "A User Telnet--Description of
an Initial Implementation" [9 August 71, RFC 206, NIC 7176]. Net
currently houses a set of operators for system-call-level interaction
with UCSB's NCP, a User Telnet, and an operator (invoked by ID on
Level II), which returns the status of Network hosts.
Staff members at the Computer Center will be happy to field questions
about OLS from Network users. In particular, an OLS consultant is
available for such purposes at (805) 961-4044. Questions about OLS,
including those specific to use of the System through the Network,
may also be addressed to Jim White, UCSB's Technical Liaison, at
(805) 961-3454 (if necessary, messages can be left at the Computer
Center Office, (805) 961- 2261).
IV. System Access
The Network user is encouraged to explore the System and is invited
to do so with the following accounting parameters:
User Number: 196
Id Number: 57372
User Name: ARPA
Problem Name: (affiliation)-(name)
in 16 characters or less
(e.g., UCSB-White)
Such use of the System will not be billed. Production users are
asked to establish their own accounts with the Computer Center ((805)
961-2261), the use of which will be billed in accordance with the
then-current rate structure.
V. Software Structure
This document is the description of a Network front-end to the Online
System, logically distinct from OLS itself. This front-end is
hereafter referred to as NETOLS. NETOLS is always responsive to
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RFC 216 Telnet Access To UCSB's On-Line System September 1971
connection requests direct4ed to socket 1. When contacted by a
Network user, NTCLS performs the Network functions required to
establish a duplex connection to him. The number of such duplex
connections (and hence the number of Network users) is bounded by an
assembly parameter whose current value is five.
Before the Network connection is established, NETOLS secures for the
user a port into OLS. Sixty-four such ports exist and are shared by
local, dial-up, and Network users. Should none be available, NETOLS
will abort the connection sequence.
Once a port has been secured and a Network connection established,
NETOLS will effectively push the _SYST_ key for the user by
transmitting to OLS the 8-bit code representing that key. A login
sequence is thus initiated and the user is transmitted the lines:
UCSB ON-LINE SYSTEM
ENTER USER NUBMER
to which he should respond with his user number. Beginning at this
point in time and continuing for the life of the Network connection,
NETOLS's sole function is that of interpreter--interpreting input
from the user and making it meaningful to the user (it is at this
point, for example, that curvilinear and special-character display
are discarded).
When the user breaks his Network connection to NETOLS, if eh hasn't
logged out of OLS already, NETOLS performs that function for him by
pushing_ SYST_ _DOWN_, just as it pushed the initial _SYST_. The OLS
port acquired for the user is then released, and hence available for
use by other users. It should be noted that the user can log out of
OLS and back on again without the Network connection's being broken,
since that action is transparent to NETOLS, who attaches no special
significance to the Key sequence, which accomplishes it.
VI. Virtual OLS Keyboard
A major function of NETOLS is to provide a mapping between elements
of the Telnet character set and the keys on an OLS keyboard (Figure
1). The lower, or operand portion of that keyboard is fairly easily
represented, since it's similar to a standard typewriter keyboard.
Most of the keys on the lower keyboard are mapped on a one-for-one
basis from elements of the Telnet character set. Upper-case
alphabetics are mapped into the alphabetics, lower-case, and
miscellany of punctuation into itself. All such one-for-one mappings
are depicted in Figure 2. A line of that figure reads as follows:
For ['half arrow' - see the PDF version of this RFC]:
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RFC 216 Telnet Access To UCSB's On-Line System September 1971
The key labeled ['half arrow'] (meaning logical not) on the lower
portion of an OLS keyboard is struck by causing the user's User
Telnet to transmit '~' (tilde).
Those lower-keyboard keys not listed in Figure 2, and _all_ the keys
on the upper- keyboard (hereafter referred to collectively as _non-
standard_ keys), are represented by the Telnet user in the following
manner. For each such key, a character string has been defined; the
string is called the _name_ of the key. In most cases, the name of a
key is identical to its label in Figure 1. The name of the _SIN_
key, for example, is 'SIN (in the Online System User's Manual,
upper-keyboard keys are denoted by underscoring their labels, to
distinguish, for example, the key _SIN_ from the three keys 'SIN').
Every non-standard key on the OLS keyboard is struck by typing its
name (or any unique abbreviation thereof), preceded by a special
_prefix_ character and followed by a space.
NETOLS interprets the prefix, name, and space from them generates a
single, 8-bit code, which forwards to OLS.
The default prefix character is semi-colon (';'), chosen simply
because for touch typists it's one of the home keys. The prefix can
be changed by the user to any character listed in Figure 2. The
procedure for so doing is described in Section VII-B. To send the
prefix character through NETOLS to OLS, type it twice in succession.
Thus, if the default prefix is in effect, ';;' is mapped into a
single semi-colon and relayed to OLS.
The names of all non-standard keys are listed in Figure 3. A line of
that figure reads as follows:
For _SIN_:
They key denoted _SIN_ in the OLS User's Manual (the trigonometric
function sine) is named 'SIN', and hence is struck by typing
'SIN', preceded by the prefix and followed by a space.
Assuming, then, that the default prefix ';' is in effect, SIN is
struck by ';SIN_' ('_' is used here and in following examples to
denote a space). Furthermore, if the user chooses, he may abbreviate
that as ';SI_', since the key desired remains uniquely identified.
Further abbreviation (to ';S_') is unsatisfactory and hence
disallowed since the single character 'S' is insufficient to
distinguish between a number of keys whose names begin with that
character. Key names may be typed by the user in either upper- or
lower-case.
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RFC 216 Telnet Access To UCSB's On-Line System September 1971
As each character of a non-standard key's name is typed by the user,
NETOLS consults it table of key names. If the character string so
far specified cannot possibly lead to a valid name, the most recent
character is ignored ('?' echoed). Hence, typing ';SJIN_' will be
accepted as _SIN_, the erroneous 'J' being ignored (and a question
mark echoed), and the subsequent 'JN_' accepted. If when the
terminating space is typed, no single key is uniquely identified a
'?' is echoed and the space ignored. Thus, ';S_I_' will be
recognized as _SIN_; the first space is
To Push (OLS Explanation) Send (Telnet Explanation)
0-9 Decimal Digits 0-9 Decimal Digits
A-Z Alphabetics A-Z UC Alphabetics
_-5 Greek Characters a-z LS Alphabetics
! Exclamation Mark ! Exclamation Mark
+ Plus Sign + Plus Sign
_ Underscore _ Underscore
- Minus Sign - Minus Sign
@ Commercial At @ Commercial At
/ Slash / Slant
# Number Sign # Number Sign
' Apostrophe ' Apostrophe
& Ampersand & Ampersand
$ Dollar Sign $ Dollar Sign
* Asterisk * Asterisk
% Percent % Percent
= Equal Sign = Equal Sign
TAB Horizontal Tab HT Horiz. Tab. (_[)
: Colon : Colon
; Semi-Colon ; Semi-Colon
[ Left Bracket [ Left Bracket
] Right Bracket ] Right Bracket
( Left Parenthesis ( Left Parenthesis
) Right Parenthesis ) Right Parenthesis
< Less Than < Less Than
> Greater Than > Greater Than
, Comma , Comma
" Quotation Marks " Quotation Marks
? Question Mark ? Question Mark
[half arrow] Logical Not ~ Tilde
| Logical Or | Vertical Line
BACK Backspace BS, DEt Backspace/Rubout
RETURN Carriage Return CR Carr. Return (_M)
SPACE Space SP Space
Figure 2. Keys With One-for-One Mappings
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To Push (OLS Explanation) The Key Name Is
[circle .] Multiply * 1
[circle +] Add +
[circle -] Subtract -
RETURN Carriage Return .
[circle /] Divide /
L0 Level 0 0
LI Level I 1
L II Level II 2
L III Level III 3
L IV Level IV 4
L V Level V 5
L VI Level VI 6
L VII Level VII 7
[circle +] Add ADD 2
ARC Argument ARG
ATAN Arc Tangent ATAN
BACK Backspace BACK 3
CASE Case CASE
[cent sign] Cent SignCENT
CLR Clear Tab CLEAR
CMPLX Complex CMPLX
CON Contract CON
CONJ Conjugate CONJ
CONV Convolve CONV
COS Cosine COS
CTX Context CTX
DEL Delta DEL
DIFF Forward Difference DIFF
DISPLAY Display DISPLAY
[circle /] Divide DIV 4
DWN Down DOWN
ENL Enlarge ENL
ENTER Enter ENTER
ERASE Erase ERASE
ESCAPE Escape ESCAPE
EVAL Evaluate EVAL
EXP Exponentiate EXP
NETOLS Command FULLDUPLEX 5
NETOLS Command HALFDUPLEX
NETOLS Command HELP
ID Identity ID
INV Invert INV
[down arrow] Line Feed Down LFDN
[up arrow] Line Feed Up LFUP
Figure 3. Keys Represented As Strings
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To Push (OLS Explanation) The Key Name Is
LIST List LIST
LOAD Load LOAD
LOG Logarithm LOG
NETOLS Command LOGOUT
LS Left Shift LS
MAX Maximum MAX
MOD Modulus MOD
[circle .] Multiply MULT 6
NEG Negate NEG
[half arrow] Logical Not NOT 7
| Logical Or OR 8
PRED Predicate PRED
NETOLS Command PREFIX
PROD Running Product PROD
PT Point PT
PWR Power PWR
REAL Real REAL
REFL Reflect REFL
REPT Repeat REPT
RESET Reset RESET
RETURN Carriage Return RETURN 9
RS Right Shift RS
0-9 Superscript 0-9 S0-S9
SEL Select SELECT
SET Set Tab SET
NETOLS Command SHIFT
SIN Sine SIN
SORT Sort SORT
SQ Square SQ
SQRT Square Root SQRT
NETOLS Command STATE
STORE Store STORE
SUB Substitute SUB
[circle -] Subtract SUBTRACT 10
SUM Running Sum SUM
SYST System SYST
TEST Test TEST
TYPE Type TYPE
NETOLS Command UNSHIFT
UP Up UP
USER User USER
Figure 3 (cont'd) Keys Represented As Strings
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RFC 216 Telnet Access To UCSB's On-Line System September 1971
1. Alternate names for [circle .], [circle +], [circle -], RETURN,
and [circle /] are 'MULT', 'ADD', 'SUBTRACT', 'RETURN', and 'DIV',
respectively. RETURN can also be represented as the single
character CR (carriage return), as indicated in Figure 2.
2. An alternate name for [circle +] is '+'
3. Alternates for BACK are the single characters BS (backspace) and
DEL (rubout), as indicated in Figure 2.
4. An alternate name for [circle /] is 'DIV'.
5. NETOLS commands are explained in Section VII.
6. An alternate name for [circle .] is 'MULT'.
7. An alternate for '[half arrow]' is the single character '~'
(tilde), as indicated in Figure 2.
8. An alternate for '|' is the single character '[2 vertical lines]'
(vertical line), as indicated in Figure 2.
9. An alternate name for RETURN is '.' RETURN can also be represented
as the single character CR (carriage return), as indicated in
Figure 2.
10. An alternate name for [circle -] is '-'.
Notes for Figure 3.
Ignored (and a '?' echoed, indicating that 'S' alone is ambiguous).
At any point in the entry of a key name, either Altmode (ESC) or '?'
may be typed by the user. NETOLS will then determine whether a key
has been uniquely specified by the characters already typed. If so,
it will echo the remaining characters of the key's name, and consider
them entered by the user. A subsequent space from the user will
cause the indicated key to be pushed. If no single key is uniquely
specified, NETOLS will echo Bel, causing a bell to be run on many
terminals. More of the key name is then expected from the user.
If after at least one character of the key name has been entered by
the user and accepted by NETOLS (and before the terminating space is
typed) the prefix is typed a second time, all already entered
characters of the name are discarded by NETOLS. Thus ';CO;SIN_' is
interpreted as _SIN_. If a carriage return is typed in the same
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RFC 216 Telnet Access To UCSB's On-Line System September 1971
context, the initial prefix will also be discarded. Hence, ';CO%S'
('%' denotes carriage return) is interpreted as the lower-keyboard
key 'S'.
VII. NETOLS Commands
A number of commands to LETOLS are defined and all are described in
this section. The format for each such command is the same as that
for the non-standard keys, and hence the command keywords are
included in Figure 3. All of the conventions of Section VI apply as
well to the entry of commands. The user should understand, however,
that such commands are processed by NETOLS, not OLS, and that they
are defined only for Network users of OLS.
A. HELP
The HELP command (invoked with ';HELP_' if';' is the prefix)
reproduces for the user the third column of Figure 3; the names of
all non-standard keys and the keywords for all defined NEOLS commands
are listed in their collating sequence on the user's virtual
teletype.
B. PREFIX
Issuing the PREFIX command causes the next character typed to become
the prefix, provided it is one of those listed in Figure 2.
Consequently, ';PREFIX_@' makes '@' the prefix, '@PREFIX_;' restores
the defaults situation.
C. SHIFT and UNSHIFT
The SHIFT command causes a perturbation of lines 2 and 3 of Figure 2.
After SHIFT is issued, all subsequent upper-case alphabetics are
mapped into the Greek characters (rather than into the alphabetics),
and lower-case alphabetics into alphabetics (rather than into the
Greek characters). This convention change may be found convenient if
the user's User Telnet sends lower-case alphabetics by default, and
requires, for example, that a shift key be held down to send upper-
case characters.
The UNSHIFT command nullifies the effect of SHIFT.
D. FULLDUPLEX and HALFDUPLEX
Issuing the FULLDUPLEX command causes all subsequent characters typed
by the user to be echoed by _NETOLS_. HALFDUPLEX nullifies the
effect of FULLDUPLEX, disabling echo by NETOLS. Half-duplex is the
default situation.
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RFC 216 Telnet Access To UCSB's On-Line System September 1971
E. STATE
The STATE command causes the current prefix, the mode of operation
('HALFDUPLX' or 'FULLDUPLEX'), and the case convention ('SHIFT IS ON'
or 'SHIFT IS OFF') to be displayed on the user's virtual teletype in
the following form:
PREFIX IS;
HALFDUPLEX
SHIFT IS OFF
F. LOGOUT
Issuing the LOGOUT command causes the user to be logged out of OLS
(i.e., _SYST_ _DOWN_ to be pushed) and his Network connection to
NETOLS to be broken. About three seconds elapse between the two
events.
VIII. OLS Display
NETOLS suppresses all but alphameric display before it reaches the
user. Alphameric display is mapped into the Telnet character set
according to Figures 4 and 5. Figure 4 lists all those OLS display
character, which have one-for-one mappings. A line of that figure
reads as follows:
For '[half harrow]'
The character logical not, displayed as '[half arrow]' on an OLS
terminal, is represented in Telnet as '~' (tilde).
Alphabetics are mapped into upper-case alphabetics and Greek
characters into lower-case alphabetics. Numerics are mapped into
numerics, and a miscellany of punctuation into itself. In addition a
number of carriage control characters are appropriately mapped-- line
feed down into LF, TAB into HT, BACK into BS, etc.; line feed up is
suppressed. ERASE is represented as Bel.
Figure 5 lists those OLS display characters which are mapped into
strings of Telnet characters. In most cases, these character strings
are stylistic representations of characters peculiar to OLS. For
example, the _ADD_ key is normally displayed in List mode as '[circle
+]'. In this Telnet implementation, '(+)' is an attempt to represent
that graphic. Superscripts are represented as underscored numerics.
Carriage return is represented as CR LF. No attempt is made to
effectively represent RS which, on an OLS display device, repositions
the beam to the upper left corner of the screen; it is made
equivalent to carriage return.
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IX. Instructing a User Telnet
For local users, all echoing _that's done at all_
To Display (OLS Explanation) OLS Sends (Telnet Explanation)
0-9 Decimal Digits 0-9 Decimal Digits
_-Z Alphabetics A-ZUC Alphabetics
_-5 Greek Characters a-z LC Alphabetics
! Exclamation Mark ! Exclamation Mark
+ Plus Sign + Plus Sign
_ Underscore _ Underscore
- Minus Sign - Minus Sign
@ Commercial At @ Commercial At
/ Slash / Slant
# Number Sign # Number Sign
' Apostrophe ' Apostrophe
& Ampersand & Ampersand
$ Dollar Sign $ Dollar Sign
* Asterisk * Asterisk
% Percent % Percent
= Equal Sign = Equal Sign
TAB Horizontal Tab. HT. Horiz. Tab (_I)
: Colon : Colon
; Semi-Colon ; Semi-Colon
[ Left Bracket [ Left Bracket
] Right Bracket ] Right Bracket
( Left Parenthesis ( Left Parenthesis
) Right Parenthesis ) Right Parenthesis
< Less Than < Less Than
> Greater Than > Greater Than
, Comma , Comma
" Quotation Marks " Quotation Marks
? Question Mark ? Question Mark
[half arrow] Logical Not ~ Tilde
| Logical Or |
| Vertical Line
BACK Backspace BS Backspace
SPACE Space SP Space
ENL/[up arrow] Line Feed Up
CON/[down arrow] Line Feed Down LF Line Feed ([up arrow]J)
_ List Mode Space _ Underscore
[shaded rectangle] List Mode Rubout X Upper-case X
_ List Mode Pointer _ Underscore
BREAK Break SP Space
ERASE Erase BEL Bell (_G)
Figure 4. Characters With One-for-One Mappings
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To Display (OLS Explanation) OLS Sends
: Post List (:)
[circle +] List Mode Add (+)
[circle -] List Mode Subtract (-)
[circle .] List Mode Multiply (*)
[circle /] List Mode Divide (/)
[arrow] List Carriage Return ([2 vertical lines])
RETURN Carriage Return CR LF
RS Reset to Upper Left CR LF
[cent sign] Cent Sign C BS [2 vertical lines]
0-9 Superscript 0-9 0 BS _
-
9 BS _
Figure 5. Characters Which Map Into Strings
is done by OLS; the terminal never echoes. In general, OLS does not
echo the user's input. There are exceptions to this rule, but they
are relatively few in number and occur primarily on the SYST level.
In particular, upper keyboard keys are never echoed except in List
mode. The Network user is advised to instruct his telnet to operate
in full-duplex mode, i.e., to echo nothing. The FULLDUPLEX command
provided by NETOLS is provided because it can be provided, but its
use is not recommended.
OLS is meant to be used in character-at-a-time mode, and the user
should so instruct his User Telnet. For those users provided with
only a line-at-a-time mode, the end-of-line character should not be
transmitted to NETOLS.
NETOLS flushes without comment all Telnet control characters it
detects in the input stream. Characters in the Telnet character set
which have no meaning to NETOLS are echoed as '?' and discarded.
Exceptions are LF (line feed) and NUL, which are flushed without
comment.
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RFC 216 Telnet Access To UCSB's On-Line System September 1971
X. Examples
A. LOGON
The dialogue which logs a user onto OLS, assuming the user number of
Section IV, is as followings:
TELNET ENTRY OLS QUERY/RESPONSE
UCSB ONLINE SYSTEM
ENTER USER NUBMER (196)
196% ID NUMBER=
57372% USER NAME= (ARPA)
ARPA% JOB NAME= (UCSB-WHITE)
UCSB-WHITE% AUTOSAVE CODE = integer
MOLSF % LOAD (MOLSF)
FILE LOADED
In this and succeeding examples, '%' denotes CR (carriage return).
Entries echoed by OLS are enclosed in parentheses above. The user
should substitute for 'UCSB-WHITE' his own affiliation and name. The
procedure above loads the math subsystem of OLS. To load instead
either COL or NET, substitute its name for 'MOLSF'. To load a
different subsystem (say COL) after logging in:
TELNET ENTRY OLS QUERY/RESPONSE
;SYST_ WORK AREAS UPDATED
;LOAD _COL% LOAD (COL)
FILE LOADED
Again, '_' denotes a space, not an underscore.
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RFC 216 Telnet Access To UCSB's On-Line System September 1971
B. NEWTOWN-RAPHSON SQUARE ROOT APPROXIMATION
A simple user program can be constructed to approximate the square
root of a number N using the Newton-Rapshon iteration procedure,
which derives the (k+1)th approximation from the kth by the following
algorithm:
X k+1= (xk+n/kk)/2
The following entries construct the user program:
;LIST_)TYPE_%ENTER_N
;1_;REAL_;LOAD_;ENTER_;STORE_N
;TYPE_% ENTER_FIRST_GUESS
;1_;LOAD_;ENTER_;STORE_X
;TYPE_%#_OF_INTERATIONS?
;0_;LOAD_;ENTER_;STORE_N
;1_;REPT_(;LOAD_N ;/_X;+_X ;/_2
;STORE_X ; DISP_%/_X ;+_X ;/_2
;LIST_;STORE_;USER_;1_;SQRT_
To display the user program, enter:
;USER_;DISP_;SQRT_
When executed, the program obtains from the user the number N whose
square root is sought, an initial guess, and the number of iterations
to be performed. The program then computes and displays the results
of each iteration, and then calls itself, permitting a second square
root to be computed. The program is executed as follows:
TELNET ENTRY OLS QUERY/RESPONSE
;USER_;1_;SQRT_ ENTER N
3 ;ENTER_ ENTER FIRST GUESS
1 ;ENTER_ #OF ITERATIONS?
4 ;ENTER_ 2. +00
1.75 +00
1.73214+00
1.73205+00
ENTER N
etc.
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RFC 216 Telnet Access To UCSB's On-Line System September 1971
C. Remote Job Entry
A file of card images can be constructed with the help of the COL
subsystem of OLS ard submitted as a batch job. Assuming COL has been
loaded, the following entries construct a card file which invokes the
Fortran compiler:
;2_//jobname_JOB_(acct#,name , , , , , ,T) ; STORE_
//_EXEC_FORTGCLG ; STORE_
//FORT.SYSIN_DD_* ; STORE_
source-statement-1 ;STORE_
...
source-statement-N ; STORE_
/* ; STORE_
To display the completed file, type:
;3_;DISP_%
To submit the file, type:
;4_;SUB_%
To watch for it in execution, type:
;DISP_J%%%...
When execution is complete, 'printed' output can be retrieved with
the following dialogue:
TELNET ENTRY OLS QUERY/RESPONSE
;CMPLX_;LOAD_ UNIT = (2314)
2314% VOL=SER= (MVT180)
MVT180% DSNAME= (RJEOUT)
RJEOUT% MEMBER= (jobname)
Jogname% NOW LOADING
FILE LOADED
The output can then be examined by entering:
;2_;DISP_1%%%...
NOTE: Text within brackets describes non-ASCII characters that were
part of the original document. Please see the PDF file for the
original representation.
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Telnet Access to UCSB's On-Line System
RFC TOTAL SIZE: 37570 bytes
PUBLICATION DATE: Thursday, January 7th, 2010
LEGAL RIGHTS: The IETF Trust (see BCP 78)
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