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Disclaimer: I am not responsible for what people (other than myself) write in the forums. Please report any abuse, such as insults, slander, spam and illegal material, and I will take appropriate actions. Don't feed the trolls.

Jag tar inget ansvar för det som skrivs i forumet, förutom mina egna inlägg. Vänligen rapportera alla inlägg som bryter mot reglerna, så ska jag se vad jag kan göra. Som regelbrott räknas till exempel förolämpningar, förtal, spam och olagligt material. Mata inte trålarna.

Aug 2021

The TTY demystified

Ben in Seattle
Mon 2-Aug-2021 03:49
I wonder when I'm in bash and erasing text with backspace what stops me from erasing the bash prompt at the beginning of the line?

That's an excellent question!

Modern terminals only show what they receive, not what they send. When you hit a key, the terminal sends it to your UNIX box which then interprets it and (usually) sends it back. The illusion that what you type immediately shows up on the terminal is due to your shell choosing to echo back the keys you've hit. The backspace character (^H) is echoed back just like any other key by your shell until there is nothing left to erase except the prompt. At that point the shell simply chooses to not echo the backspace, thus keeping the prompt intact. Some shells even choose to send a different character, ^G, which rings the bell on the terminal to let you know you've hit the end.
Ben in Seattle
Mon 2-Aug-2021 04:18
Great article.
For another great source on TTY devices you can go to:


That site has been revamped and IBM only offers the manuals in PDF format. You can now (2021) find the TTY Subsystem for AIX documentation here:


Music For Microcontrollers

Tue 17-Aug-2021 16:16
Really nice to see the tunes on Spotify to have simpler access to them even if I'm often listening to chipmusic radio all day anyway.

The remastering is really nice overall and the reduced noise and clicks are really a plus. I do kind of miss the old triangle bass where the (what I guess is) quantization noise gave it a bit more texture like from the NES's soundchip.

Either that or I'm just so used to the old ones that I just don't like difference at all :P.

Amazing compositions anyway as usual. Would buy an actual EP if it became available.

P.S. Greetings from an wind band colleague from your time as a drummer/percussionist in "Praktorkestern". Still remember your piano solo in the Earth Wind and Fire medley.

The TTY demystified

Tue 17-Aug-2021 19:49
So as a convenience, the operating system provides an editing buffer and some rudimentary editing commands (backspace, erase word, clear line, reprint)

Can anybody supply examples of how these listed commands may be applied to an incoming command? When can the machine decide to deprive the command of all word (i.e. erase it from the command)?


Sat 21-Aug-2021 03:12
Finally put a VIC II squared and a 6569R5 in my USA C64 and I remembered this from back in 2012 and knew what I had to try first. You a real treasure, thank you!
Sat 21-Aug-2021 03:17
Finally put a VIC II squared and a 6569R5 in my USA C64 and I remembered this from back in 2012 and knew what I had to try first. You a real treasure, thank you!
Darn autocorrect - you *are* a real treasure