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tutorials:tops20-interactive [2011/04/30 15:08]
clemens
tutorials:tops20-interactive [2012/05/01 20:06]
ivan Does not apply to SDF-EU.
Line 23: Line 23:
 |  | ^C | Exit program (may need 2 or more) | |  | ^C | Exit program (may need 2 or more) |
  
-===== TOPS20 Tutorial Log =====+Does not apply to SDF-EU.
  
-<​code>​ +$Id: tops20-interactive.html,​v 1.1 2010/05/23 16:55:57 papa Exp $
-  @tops20+
  
-  Following is  a brief  explanation of  some conventions ​ of  Tops-20. 
-  Learning and remembering them will be a great help when exploring the 
-  facilities on this system. ​ If you are already familiar with Tops-20, 
-  you should ​ ^C out of this program. ​  If not,  you might want to take 
-  notes. 
- 
-  The first things you should learn  are the control characters ^S  and 
-  ^Q.  A  "​control character" ​ is made  by striking ​ some letter ​ WHILE 
-  HOLDING DOWN the control key  (marked "​CTRL"​). ​ They are  represented 
-  in print by putting ^ before the letter. ​ So ^S is made by striking S 
-  while holding down the CTRL key. (S need not be typed in upper case.) 
- 
-  ^S and ^Q are used to stop and start output (typing) to the terminal. 
-  This is useful ​ mostly on a  CRT (video) terminal, ​ where things ​ you 
-  want to look  at have  a habit  of going off  the top  of the  screen 
-  before you can read it. 
- 
-      ^S - stop output temporarily 
-      ^Q - continue stopped output 
- 
-  A ^S typed by you will be simulated now.  (Type ^Q to continue.) 
- 
-  Very good!  It is also  possible (but we won'​t ​ go into how here)  to 
-  have the line set up so that it automatically pauses at the end of an 
-  uninterrupted page  of output. ​  ​Practice using  ^S and  ^Q every  so 
-  often throughout this lesson. ​ (Remember: When output stops where you 
-  wouldn'​t expect it to,  the system is frequently ​ just waiting for  a 
-  ^Q.) 
- 
-  The next concept you  should learn is that  of ESCAPE and "?"​. ​  Most 
-  commands are given  with words. ​  You needn'​t type  out the  complete 
-  command. ​ A  unique abbreviation ​ is  sufficient. ​ After  typing ​ the 
-  abbreviation,​ an ESCAPE (sometimes ​ called ALTMODE, labeled "​ESC" ​ or 
-  "​ALT"​) will cause  the system ​ to type out  the rest  of the  command 
-  word.  This is called recognition. 
- 
-      ESC - complete an abbreviated command 
- 
-  Here is  an example ​ - type  an ESCAPE at the end of this example: 
- 
-  TOPS20&​gt;​recogNITION 
- 
-  Good.  See  how the  system completed ​ the word  for you?   ​There ​ is 
-  another advantage ​ to using  ESCAPE for  recognition -  guide  words. 
-  When you type ESCAPE ​ to recognize a command, ​ the system will  often 
-  supply a hint as to  what it wants to  see next.  These hints, ​ which 
-  are always typed in parentheses,​ are called guide words. ​ Try  typing 
-  ESCAPE again and see how it works: 
- 
-  TOPS20&​gt;​gUIDE (WORDS) 
- 
-  Alright! ​ The "​(WORDS)"​ above is an  example of a guide word.   Guide 
-  words are also sometimes ​ called noise words. ​ Usually they give some 
-  hint as to what should come next, as 
- 
-      TYPE (FILES) ​      - you should give it names of files to type 
-      LOGIN (USER) ​      - you should type your user name 
- 
-  Sometimes, though, this doesn'​t give a  big enough hint.  If this  is 
-  the case, you can find out what  is expected of you next by typing ​ a 
-  question mark. 
- 
-      ? - show what is expected here 
- 
-  Ok, now try out using a question mark ("?"​). ​ (If the system ​ doesn'​t 
-  do anything when you're done, type a carriage return.) 
- 
-  How do you spell 3? ? one of the following: 
-   ​ONE ​    ​THREE ​   TWO 
-  How do you spell 3? three 
- 
-  Ok, next we'll work on changing what you've typed in.  First of  all, 
-  sometimes, the line you are entering gets broken or messed up in some 
-  other way.  If you type a ^R,  the system will retype the prompt ​ and 
-  any input you have typed. 
- 
-      ^R - retype the current line 
- 
-  Here a  broken line  will be  demonstrated. ​  Type a  ^R to  have  it 
-  redisplayed. 
- 
-  TOPS20&​gt;​This line is 
-  SANTA.CLAUS,​ TTY45, 23-May-2010 5:41AM 
-  Have you been good? 
-  TOPS20&​gt;​This line is not broken 
-  There -  you  see  how  the  line  got  retyped ​ all  in  one  piece? 
-  Sometimes, something you  typed was  not what you  meant. ​ There  are 
-  special characters which  you can  use to  edit what  you have  typed 
-  already. ​ The first of these is DELETE (which may also be labelled as 
-  either "​DEL",​ "​RUBOUT",​ or "​RO"​). ​ Its function is to erase the  last 
-  character typed. 
- 
-      DEL - erase the previous character 
- 
-  Use a DELETE to correct the following error: 
- 
-  TOPS20&​gt;​correction 
- 
-  Hey, you're moving right along now.  The next line editing ​ character 
-  to learn is ^W.  Sometimes your mistake doesn'​t involve just the last 
-  couple of letters. ​ Sometimes you'll goof up a word or two.   ​DELETEs 
-  aren't convenient when you have to  delete so many letters. ​ ^W  will 
-  delete characters a word at a time. 
- 
-      ^W - erase the previous word 
- 
-  Use one or more ^W (along with some other features you've learned) to 
-  correct the following error: 
- 
-  TOPS20&​gt;​This example is not wrong 
- 
-  That's it!  Almost done with  the editing control characters... ​  The 
-  last of these is ^U.  If, somehow, ​ the line you typed in was not  at 
-  all what you were intending to type, ^U will erase the entire line of 
-  input. 
- 
-      ^U - erase the entire line 
- 
-  Use ^U  (and  some other  features ​ you've learned) ​ to  correct ​ the 
-  following error (we're getting tricky now): 
- 
-  TOPS20&​gt;​ 
- 
-  Wonderful! ​ Now you know all about editing characters for commands on 
-  Tops-20. ​ Only a couple more things to learn. ​ The next is ^O.  If  a 
-  lot of typing is coming out on your terminal which you don't want  to 
-  see, but you don't want to  interrupt the program which is doing  the 
-  output (we'll get to how to do  that in a minute), you should type  a 
-  ^O.  The  first  time you  type  ^O,  it redirects ​ output ​ for  your 
-  terminal off into  nowhere (sort of  sends it to  the "​bit ​ bucket"​). 
-  The next time you type ^O,  output is directed back to your  terminal 
-  again. ​ All output in the interim is lost. 
- 
-      ^O - toggles output suppression 
- 
-  For practice with  ^O, I'​m ​ going to  dump a  lot of  output to  your 
-  terminal. ​ Try typing a few ^O's to see how they work. 
- 
-  Type carriage return when you're ready. 
-  This is trip number 1 thru the loop. 
-  This is trip number 2 thru the loop. 
-  This is trip number 3 thru the loop. 
-  This is trip number 4 thru the loop. 
-  This is trip number 5 thru the loop. 
-  [...] 
-  This is trip number 46 thru the loop. 
-  This is trip number 47 thru the loop. 
-  This is trip number 48 thru the loop. 
-   ​^O...s trip number 49 thru the loop. 
-  he loop. 
-  This is trip number 53 thru the loop. 
-  This is trip number 54 thru the loop. 
-  [...] 
-  This is trip number 98 thru the loop. 
-  This is trip number 99 thru the loop. 
-  This is trip number 100 thru the loop. 
- 
-  So there'​s ^O for you.  Quite useful at times, isn't it... 
- 
-  Would you like to try it again? no 
- 
-  Ok, one last thing which you'll find useful before the final  lesson. 
-  That's ^T.  ^T  tells you  information about what  you are  currently 
-  doing. ​ It's output looks something like this: 
- 
-  17:03:57 TOPS20 IO wait at 2332  Used 0:34:41.4 in 10:05:05, Load 
-  3.58 
- 
-  In the above example, "​TOPS20"​ is  the the name of the program ​ which 
-  you are running. ​  "​IO wait" tells  what the program ​ is doing. ​  (In 
-  this case, it's waiting for some input or output to complete -  maybe 
-  waiting for the user to  type something.) ​ The number following ​ "​at"​ 
-  is the  address ​ at  which  the program ​ is  executing. ​  ​The ​ number 
-  following "​Used"​ is the amount of time your program(s) have  actually 
-  spent running, and the one after "​in"​ is how long you've been  logged 
-  on.  The  number following ​ "​Load"​ is  roughly the  number of  people 
-  trying to use the machine "right now." 
- 
-  Try typing a ^T... 
- 
-   ​05:​36:​28 TOPS20 SLEEP at PS5+11 ​ Used 0:00:01.5 in 0:07:49, Load 
-  0.03 
- 
-  Well, would  you believe ​ you've made  it to  the last  part of  this 
-  lesson? ​ The last (but not  least important) thing you'll learn  here 
-  is about ^C.  Typing ^C's is how you get out of almost any program on 
-  Tops-20. ​ If the program is waiting for input, one ^C will  interrupt 
-  it.  If not, probably ​ two will work, but  sometimes as many as  four 
-  are needed. ​ ^C is usually used as a panic exit from a program. 
- 
-      ^C - exits (immediately) from the program 
- 
-  Oh, yes... ​ Before you try it out, if you'd like to run this  program 
-  again sometime, it's TOPS20:​TOPS20.EXE. 
- 
-  Ok - Now for the last bit of practice - ^C out of this program. 
-  ^C 
- 
-  To summarize: 
- 
-      ^C  - Cease program immediately 
-      ^O  - Output suppress 
-      ^Q  - Qontinue output 
-      ^R  - Redisplay line 
-      ^S  - Stop output 
-      ^T  - Tells what's happening 
-      ^U  - Undoes line being typed in 
-      ^W  - Word deletion 
-      ?   - what?s expected here 
-      DEL - DELetes one character 
-      ESC - rESCognitiion invoked 
- 
-  Ok, good luck... 
-  @ 
-</​code>​