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2023-06-30.log
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<muurkha>while it is true that you can't punch every hole, I think you can punch more than the traditional one byte per column <muurkha>oriansj: yeah, paper tape was popular for personal computers, but punched cards never were <muurkha>my wife and I decoded some ITA2 punched paper tape the other day <muurkha>when I dialed into BBSes from a CP/M machine, I set up the modem as devices PUN: and RDR: <muurkha>I think more generally punched paper tape was popular on minicomputers. the Teletypes they used for consoles had built-in punching and reading capabilities <oriansj>as I understand it, paper tape was harder than punched cards to edit but cheaper and simpler but the machines for punched cards were more expensive, more complex and faster. <muurkha>Tom Jennings said that they came from two different traditions <muurkha>punched cards for business data processing are from like 01888, more than 50 years before computers <muurkha>IBM was a punched-card company before it was a computer company <oriansj>I see things about higher end systems being able to accept cards in any order and use the line numbers on the cards to reorder them on load <muurkha>no, a card sorter was not a higher-end system <muurkha>it was just a routine piece of back-office equipment <muurkha>punched paper tape, by contrast, came from the world of telegraphy <muurkha>the Teletype descended from Murray's teleprinter in 01920 <muurkha>it was oriented toward human-to-human communication <muurkha>not collating, sorting, filtering, and totaling <muurkha>and that's largely where ASCII came from: FIELDATA and Baudot-Murray code (ITA2) <muurkha>I don't really know much about the relative costs of the different kinds of equipment, but it seems likely that what you say is correct. keypunches sure *look* more expensive and complex than a Teletype <muurkha>but a different possible reason that the world shifted to Teletypes and paper tape at the same time as shifting to mini- and microcomputers is that paper tape is a better medium for everything *except* editing <muurkha>it occupies less space, it's less prone to lace-card jams, it survives more trips through the reader, it can't get out of order from being dropped on the floor, and it doesn't require breaking up your data into 80-byte records <muurkha>with that in mind, have you looked at Schorre's META II? <muurkha>one of its interesting features is that its memory requirements are limited to one input line, one output line, and the parse stack <oriansj>muurkha: I haven't seen Schorre's META II but I have seen a couple META II implementations in the past <oriansj>I guess I git cloned it prior to it getting pulled down <muurkha>looks like a faithful implementation of META-II <muurkha>though as it happens it doesn't take advantage of the property I mentioned :) <muurkha>instead it reads in the entire input file at startup <muurkha>I don't see what the difference is between loading multiple rolls of paper tape and loading multiple hoppers of punched cards, except that the tapes are a lot smaller <muurkha>well, and you get some nulls at the beginning and end of a roll, but you also have extra spaces to fill out punched cards <muurkha>it might be worth mentioning that keypunches have the ability to copy data from a previous punched card character by character <muurkha>although I think normally only into the same column! <muurkha>> According to Murphy, the initial acronym was Tape Editor and Corrector because "punched paper tape was the only medium for the storage of program source on our PDP-1. There was no hard disk, floppy disk, magnetic tape (magtape), or network." <muurkha>> On these machines, the normal development process involved the use of a Friden Flexowriter to prepare source code offline on a continuous strip of punched paper tape. Programmers of the big IBM mainframes customarily punched their source code on cards, using key punches which printed human-readable dot-matrix characters along the top of every card at the same time as they punched each <muurkha>machine-readable character. Thus IBM programmers could read, insert, delete, and move lines of code by physically manipulating the cards in the deck. Punched paper tape offered no such amenities, leading to the development of online editing. <oriansj>which ultimately are vastly superior (assuming you have enough cheap computers or cheap terminals connected to a timesharing operating system) <ekaitz>it's a c compiler written in zig <ekaitz>it doesn't really help in our goals but it's cool <oriansj>ekaitz: nope, first I am seeing it. And writing C compilers usually is a good practice for knowing a programming language. <ekaitz>oriansj: I have the LCC book at home, but I couldn't read it :) <oriansj>ekaitz: honestly I have never looked at the LCC book and having seen a dozen different ways to parse C; it doesn't surprise me <fossy>janneke: do you happen to know why R_OK = 0 in mes but R_OK = 4 in guile (and unistd.h of C)? <janneke>it doesn't seem of much consequence, the only difference/problem is would be that mes thinks it can read a file without read permissions <janneke>i guess it's mostly used to see if the file exists...