1 THIS IS A GOOD PRINT
 510 PRI "THE TAPE FOR OUR FILE.  IF IT FOUND SPACE, IT WROTE"
 520 PRI "IN THE NAME OF OUR FILE ON THE DIRECTORY AND STOPPED."
 540 PRINT
 550 INPUT "READY ?";Q
 560 IF Q$="X" THEN 1420
 580 PRINT
 590 PRI "  WE NOW HAVE THE NAME OF THE FILE WRITTEN IN THE "
 610 PRI "TABLE OF CONTENTS OF A BOOK.  NOW WE MUST WRITE THE "
 620 PRI "INFORMATIONS THAT WE WANT INTO THIS 'CHAPTER'."
 621 PRI
 630 PRI "  WE USE A PRINT STATEMENT MODIFIED BY THE '#' SIGN"
 640 PRI "WHICH TELLS THE COMPUTER THAT WE WANT TO WRITE ON THE "
 650 PRI "TAPE.  THE INSTRUCTION LOOKS LIKE THIS......"
 655 PRINT
 660 PRI TAB(15) "30 PRINT #,X$,Y$,Z$"
 665 PRI TAB(15) "40 CLOSE"
 670 PRINT
 680 PRI "THIS INSTRUCTION WILL WRITE WHAT YOU ENTERED FOR THESE"
 690 PRI "VARIABLES (YOUR NAME) ONTO THE TAPE IN THE SPACE"
 700 PRI "RESERVED FOR OUR FILE ON THE DIRECTORY."
 710 PRI "WATCH TAPE NO. 1 AS THIS INSTRUCTION IS EXECUTED...."
 715 PRI
 720 PRINT #,X$,Y$,Z$
 730 CLOSE
 740 PRINT
 750 PRI "  THE TAPE SHOULD HAVE REWOUND TO READ THE DIRECTORY"
 760 PRI "TO FIND OUT WHERE ON THE TAPE THE SPACE FOR THIS FILE"
 770 PRI "HAS BEEN ASSIGNED.  IT THEN MOVED FORWARD TO THIS "
 780 PRI "SPOT ON THE TAPE AND WROTE IN YOUR NAME AND STOPPED."
 785 PRI
 790 PRI "  AFTER THIS INSTRUCTION WE MUST CLOSE THE FILE FOR "
 800 PRI "OUTPUT SINCE THE COMPUTER CANNOT HAVE MORE THAN ONE "
 810 PRI "FILE OPEN AT A TIME."
 815 PRI
 820 PRI "  NOW LET'S RETRIEVE THIS DATA.  WE MUST FIRST"
 830 PRI "OPEN THE FILE FOR INPUT.  REMEMBER THAT THE INPUT "
 840 PRI "REFERS TO INPUT FROM THE TAPE TO THE CPU. THE INSTRUCTION"
 850 PRI "LOOKS LIKE THIS....."
 860 PRINT
 870 PRI TAB(15) "50 OPEN P$ FOR INPUT"
 890 PRI "  WE NEED TO ADD TO THIS SOME INSTRUCTIONS THAT WILL"
 900 PRI "ALSO READ THE DATA FROM THE FILE AND PRINT IT OUT FOR"
 910 PRI "USE.  THIS IS DONE WITH THESE INSTRUCTIONS..."
 915 PRINT
 920 PRI TAB(15) "60 INPUT #,X$,Y$,Z$"
 930 PRI TAB(15) "70 PRINT X,Y,Z"
 940 PRINT
 950 PRI "  WATCH THE TAPE AS THESE ARE EXECUTED...."
 951 INPUT "READY ?";D
 952 IF D="X" THEN 1420
 955 PRINT
 960 OPEN P$ FOR INPUT
 970 INPUT #,X$,Y$,Z$
 980 PRINT X$,Y$,Z$
 990 PRINT
1000 PRI "  THE DATA PRINTED CAME FROM THE STORED DATA ON THE TAPE"
1010 PRI "IN THE FILE THAT YOU CREATED.  IT WILL ALWAYS BE THERE."
1020 PRI 
1030 PRI "  TO SUMMARIZE, HERE ARE THE INSTRUCTIONS THAT ARE NEEDED"
1040 PRI "TO CREATE,WRITE AND READ A FILE ON MAGNETIC TAPE..."
1045 PRI
1050 PRI TAB(15) "10 P$='DATA'"
1060 PRI TAB(15) "20 OPEN P$ FOR OUTPUT,12"
1070 PRI TAB(15) "30 PRINT #,X$,Y$,Z$"
1080 PRI TAB(15) "40 CLOSE"
1090 PRI TAB(15) "50 OPEN P$ FOR INPUT"
1100 PRI TAB(15) "60 INPUT #,X$,Y$,Z$"
1110 PRI TAB(15) "70 PRINT X$,Y$,Z$"
1115 PRI
1120 PRI "  LET'S REASSIGN THE VARIABLES AND RUN THE WHOLE THING"
1130 PRI "AT ONE TIME, O.K.?"
1140 PRI
1150 INPUT "X$=";X$
1160 INPUT "Y$=";Y$
1170 INPUT "Z$=";Z$
1180 PRI
1190 PRI "  NOW LET 'S RUN EVERYTHING ALL AT ONCE, WATCH THE TAPES!"
1192 INPUT "READY ?";H
1195 P$="DATA"
1200 OPEN P$ FOR OUTPUT,3
1210 PRINT #,X$,Y$,Z$
1220 CLOSE
1230 OPEN P$ FOR INPUT
1240 INPUT #,X$,Y$,Z$
1250 PRINT X$,Y$,Z$
1260 PRI 
1270 PRI "  DID THE TAPE MOVE AS BEFORE?  DID YOU KNOW WHAT IT"
1280 PRI "WAS DOING?  WOULD YOU LIKE TO REPEAT ANY OF THIS AGAIN?"
1290 INPUT "(YES OR NO)";W$
1295 PRI
1300 IF W="YES" THEN 10
1310 PRI " YOU NOW KNOW ALL THERE IS TO KNOW ABOUT THE INPUT"
1320 PRI "OUTPUT OF THE PDP8 COMPUTER.  FOR MORE INFORMATION"
1330 PRI "CALL UP FROM THE $CATALOG THE PROGRAMS LISTED HERE..."
1340 PRI
1350 PRI TAB(15) "FILPUT"
1360 PRI TAB(15) "XXXXXXX"
1370 PRI 
1380 PRI "  YOU MIGHT ALSO TRY LISTING THE PROGRAMS AND DOING "
1390 PRI "A LITTLE EXPERIMENTING BY YOURSELF.  TRY IT YOU'LL"
1400 PRI "LIKE IT !!!!!"
1410 PRI "THANK YOU FOR USING THIS PROGRAM, I HOPE YOU ENJOYED IT"
1420 STOP
1430 END