Infocom on PDP-11

On Wed, 11 May 2005, Paul Koning wrote: Related, the Librascope/General Precision LGP-30 (and the LGP-21) console/paper tape input system seems bizarre today. The INPUT instruction reads tty characters and shifts them into the accumulator until it receives an apostrophe character (yes, '). The machine actually halts (well, infinite I/O wait) for each character. Computer response on each keystroke is therefore impossible. A minimum of two keystrokes (or paper tape characters) is needed for the CPU to see a "keystroke" -- KEY then ' LGP's ACT compiler (which they called fortran-like or algol-like, depending on who you asked) source code looks awful: s1'dim'a'500'm'500'q'500'' index'j'j+1'j-1'' daprt'e'n't'e'r' 'd'a't'a''cr'' rdxit's35'' s2iread'm'1''iread'q'1''iread'd''iread'n'' 1';'j'' 0'flo'd';'d.'' s3'sqrt'd.';'sqrd.'' 1'unflo'sqrd.'i/'10';'sqrd'' 2010'print'sqrd.''2000'iprt'sqrd''cr''cr'' (from http://world.std.com/~reinhold/comp-hist/actiiisample.html) Modern character-based I/O paradigms were not universal and are not the simplest. This kinda stuff was a major stumbling block for program and language development.