satiated_grue
Joined 3 years ago
Joined 3 years ago
\r\n was how lines were terminated on the wire for many early devices (for example, the Teletype ASR-33 seen in the famous photograph of Thompson and Ritchie at Bell Labs).
If the carriage is very far to the right, and an LF is sent followed by the CR, then the carriage will still be returning when the next character arrives, which will print at some random location along the return path.
CR followed by the mechanically much faster LF operation gives enough time for the carriage to be fully homed and in proper position for the printable character to be struck.
It's a humorous pointing out of "We've called them bugs for a long time, but this time it actually was a real, physical bug, and here it is - ha ha."
The myth is that people for some reason started thinking that was the first use of the word "bug" in this context.
https://en.wikipedia.org/wiki/Yggdrasil_Linux/GNU/X
Really liked Knoppix for a lot of things, though. Used to take it to the county used-sales office and boot the PCs they were selling to test for functionality and Linux compatibility.
I go to events like vintage computer festivals, and old folks are having a party with computers.
I look at younger people with computers, and for the most part they are just commodity tools for hosting apps and watching media. Even younger people describing what they are doing for fun with computers are building "home labs" of application hosting systems.
Sending a carriage return and linefeed to a TTY 33 and then printing works fine. Doing them in the opposite order, if the carriage is to the right of the page, will result in a linefeed (platen rotation) happening quickly, then the carriage starting to move left to the beginning of the next line, and then the next printed character will print wherever the carriage happens to be at the time - not yet to the left. So you will be missing a character at the beginning of the line because it's in between the two lines in an unexpected column-ish.
I have run into (in my mind, "hipster") code where the programmer for some reason reversed the order of CR and LF.
https://www.lo-tech.co.uk/wiki/IBM_Personal_Computer_XT_Syst... https://www.lo-tech.co.uk/understanding-pcxt-slot-8/