Re: [TUHS] terminal - just for fun

Remember that writing programs on terminals was a relative latecomer -- FORTRAN was designed for punched cards. Their 6-bit character set has "numbers" and "letters" (no case need apply). The printers and other supporting peripherals printed capital letters, probably because you could get legibility with fewer dots that way and didn't have to worry about descenders. At Bell Labs (before Unix days) programmers wrote their programs on coding sheets and handed them in to a room full of keypunchers. They would punch the program up on cards, and then a second person would repeat the process using a verifier, a piece of hardware that took in a punched card, and had a keyboard, and would verify that what the person typed in was what had been punched on the card. Then the punched and verified deck of cards was returned to the programmer, who could submit it to the mainframe to run it. Although the coding sheet had little tick marks to indicate the column positions, the keypunchers took advantage of FORTRAN syntax to simply ignore spaces (they did know enough to respect blanks in Hollerith strings and to start typing the program in the appropriate column). Leaving the blanks out not only made the process go faster, but also reduced the number of false failures in verification, where the original keypuncher and verifier disagreed on how many spaces should be inserted. The model 33 Teletypes that were the most common terminal attached to Unix in the early days had only a single case, as I recall, being primarily used with paper tape with a character set closely related to the character set used on punched cards (although with some features that eventually become supported in ASCII). Unix, however, interpreted the "letters" in the character set as lower case by default, which was highly unusual at that time, since there were almost no printers or terminals that would print upper and lower case.