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The Elegance of the ASCII Table

danq.me

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Re: The Elegance of the ASCII Table

#51

Post by ggm »

fsckboy wrote: post #47
ggm wrote: post #8

man ascii is never far from my fingers. combined with od -c and od -x it gets the job done. I don't think as fluently in Octal as I used to. Hex has become ubiquitous.

you mean ? ascii

No I don't -I live in a different universe to you:

  % (uname; cd /usr/ports; ls -d */ascii)
  FreeBSD
  zsh: no matches found: */ascii
  % which ascii
  ascii not found
  %
It's the same on OSX and debian by default doesn't install that command. If you live inside a POSIX/IEEE 1003 system and want to know the ascii table reliably then the command I run is the one which works. If your distribution doesn't ship manuals by default you have bigger problems.

Re: The Elegance of the ASCII Table

#52

Post by WalterBright »

Too bad we now have Unicode, an elegant castle covered with ugly graffiti and ramshackle addons. For example:

1. normalization

2. backwards running text (hey, why not add spiral running text?)

3. fonts

4. invisible characters

5. multiple code points with the same glyph

6. glyphs defined by multiple code points (gee, I thought Unicode was to get away with that mess from code pages!)

7. made up languages (Elvish? Come on!)

8. you vote for my made-up emoticon, and I'll vote for yours!

Re: The Elegance of the ASCII Table

#53

Post by jart »

WalterBright wrote: post #52

Too bad we now have Unicode, an elegant castle covered with ugly graffiti and ramshackle addons. For example: 1. normalization 2. backwards running text (hey, why not add spiral running text?) 3. fonts 4. invisible characters 5. multiple code points with the same glyph 6. glyphs defined by multiple code points (gee, I thought Unicode was to get away with that mess from code pages!) 7. made up languages (Elvish? Come…

Hey at least we got the astral planes. https://justine.lol/dox/unicode.txt

Re: The Elegance of the ASCII Table

#54

Post by jart »

kragen wrote: post #32
jolmg wrote: post #10

> So when you’re reading 7-bit ASCII, if it starts with 00, it’s a non-printing character. Otherwise it’s a printing character. > The first printing character is space; it’s an invisible character, but it’s still one that has meaning to humans, so it’s not a control character (this sounds obvious today, but it was actually the source of some semantic argument when the ASCII standard was first being discussed). Hmm..…

del is not a printing character. it's a control character. if you run a paper tape full of del characters through a teletype it does not print anything. it has to have that bit pattern, even though it greatly complicates the mechanics of the teletype (which has to do all the digital logic with cams and levers) because that way it can be punched over any character on the paper tape to delete it a figure caption in thi…

> so the only way to mark a character as invalid was to rewind the tape and punch out all the holes in that position

So that's why \177 (DEL) is the loneliest control character. Wow. Thank you!

Re: The Elegance of the ASCII Table

#55

Post by lmm »

KingOfCoders wrote: post #43

For everyone who doesn't need ä,ü,ö. Or software that needs to take ä,ü,ö. For everyone else, UTF is a blessing.

> For everyone else, UTF is a blessing.

Except people who want to use Japanese and not have it render weirdly, something that was easy in any internationalised software that used the traditional codepage system, but is practically impossible in Unicode-based software.

Re: The Elegance of the ASCII Table

#56

Post by jart »

penteract wrote: post #35
yardshop wrote: post #23

Earlier quoted context omitted.

In the DOS days, you could "type" control characters by pressing Ctrl and the corresponding letter key, Ctrl+M is Carriage Return, Ctrl+H is Backspace, Ctrl+Z is End Of File, etc. It was probably possible to type an RS with Ctrl+Shift+. and the others with similar combos.

In a desktop linux terminal, Ctrl-^ or Ctrl-~ work for me. In a tty, I need to press Ctrl-V before them.

Yeah Linux still works exactly this way. The modern WIN32 API even works that way too. When you ReadConsoleInput() it gives you teletypewriter style keyboard codes. When I wrote a termios driver for Cosmopolitan to have a Linux-style shell in CMD it really didn't take much to translate them into the Linux style. We're all still using glorified teletypes at the end of the day. It will always be the substrate of our world. One system built upon another older system.

Re: The Elegance of the ASCII Table

#57

Post by Retr0id »

WalterBright wrote: post #52

Too bad we now have Unicode, an elegant castle covered with ugly graffiti and ramshackle addons. For example: 1. normalization 2. backwards running text (hey, why not add spiral running text?) 3. fonts 4. invisible characters 5. multiple code points with the same glyph 6. glyphs defined by multiple code points (gee, I thought Unicode was to get away with that mess from code pages!) 7. made up languages (Elvish? Come…

Language itself is a pile of ugly graffiti and ramshackle addons. It would be weird if Unicode didn't reflect this.

Re: The Elegance of the ASCII Table

#58

Post by Symbiote »

jki275 wrote: post #26
yardshop wrote: post #23

Earlier quoted context omitted.

In the DOS days, you could "type" control characters by pressing Ctrl and the corresponding letter key, Ctrl+M is Carriage Return, Ctrl+H is Backspace, Ctrl+Z is End Of File, etc. It was probably possible to type an RS with Ctrl+Shift+. and the others with similar combos.

you can still type them -- alt + 030(for instance) on the keypad will insert that RS character. In Windows at least -- not sure about the other OS.

On Linux terminals entering control characters is done with the control key, Ctrl-G for example, but they will often be intercepted by the program that is running.

Bash will insert the control character (rather than interpret it) if you prefix it with Ctrl-V.

Re: The Elegance of the ASCII Table

#59

Post by Symbiote »

penteract wrote: post #33
thaumasiotes wrote: post #28

Earlier quoted context omitted.

> considering that balance feels a bit silly because if you're aware there could be a problem in a context where you could choose between commas and record separators, you could just add validation or escaping. As soon as you have validation or escaping, having a record separator character loses its entire purpose. The existence of the character is predicated on the idea that you don't have to do that, and that idea…

> As soon as you have validation or escaping, having a record separator character loses its entire purpose. The existence of the character is predicated on the idea that you don't have to do that, and that idea is false. I disagree with this - the data needs to be stored somehow, and while other characters (like comma) can be used, having a dedicated character can help - for example if the data might legitimately con…

I agree.

TSV is widely used, but lacks a way to escape the tab and new line characterss. RS-V is the same, but allows including tabs and new lines in records.

Re: The Elegance of the ASCII Table

#60

Post by Retr0id »

lmm wrote: post #55
KingOfCoders wrote: post #43

For everyone who doesn't need ä,ü,ö. Or software that needs to take ä,ü,ö. For everyone else, UTF is a blessing.

> For everyone else, UTF is a blessing. Except people who want to use Japanese and not have it render weirdly, something that was easy in any internationalised software that used the traditional codepage system, but is practically impossible in Unicode-based software.

Where can I learn more about this issue?
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