[9fans] rawon for /dev/cons

[9fans] rawon for /dev/cons

[Rudolf Sykora]

Hello,

I played with this simple program, which just sets the raw mode for
the console and writes back written characters:
--------------------------
#include <u.h>
#include <libc.h>

void
main (int argc, char *argv[])
{
	int	cfd;
	char	buf[2];
	int	nr;

	cfd = open("/dev/consctl", OWRITE);
	write(cfd, "rawon", 5);

	while((nr = read(0, buf, 1)) > 0) {
		if(buf[0] == 'q') break;
		buf[1] = 0;
		print("%s", buf);
	}
	close(cfd);
	exits(nil);
}
--------------------------

But I was surprised it doesn't do what I want.
The rio(1) man page says, in the 'Raw text windows' section that
'... no typed keyboard characters are special, ... and all are passed
to a program immediately upon reading'.
However, it seems rio still interprets ^u, ^a, ^e, ^w, BS, arrows,
page up/down,... (although not DEL, e.g.)
Can anybody explain to me what is wrong?
(Also I don't quite understand why pressing ^d results in drawing EOT,
pressing F1 does nothing as well as pressing alt-whatever [e.g.
alt-AE]...; Also, what must I do to see the codes (like ^a=0x01)
instead of the characters?)

Thanks a lot!
Ruda

Re: [9fans] rawon for /dev/cons

[erik quanstrom]

> But I was surprised it doesn't do what I want.
> The rio(1) man page says, in the 'Raw text windows' section that
> '... no typed keyboard characters are special, ... and all are passed
> to a program immediately upon reading'.
> However, it seems rio still interprets ^u, ^a, ^e, ^w, BS, arrows,
> page up/down,... (although not DEL, e.g.)
> Can anybody explain to me what is wrong?

if you open the mouse, you will supress rio's terminal from using these
keys for navigation.

> (Also I don't quite understand why pressing ^d results in drawing EOT,

you're reading ctl-d (0x04) and then printing it.  since there
is a character in your font at that position that looks like EOT, that's
what you see.

> pressing F1 does nothing as well as pressing alt-whatever [e.g.
> alt-AE]...; Also, what must I do to see the codes (like ^a=0x01)
> instead of the characters?)

a Rune is >1 byte.  you're only reading one byte.

- erik

---

#include <u.h>
#include <libc.h>

void
main(void)
{
	char buf[UTFmax + 1];
	int cfd, mfd, n, i, l;
	Rune r;

	cfd = open("/dev/consctl", OWRITE);
	if(cfd == -1 || write(cfd, "rawon", 5) != 5)
		sysfatal("consctl: %r");
	mfd = open("/dev/mouse", OREAD);
	if(mfd == -1)
		sysfatal("mouse: %r");
	i = 0;
	for(;;){
		for(;;){
			n = read(0, buf + i, 1);
			if(n <= 0)
				goto done;
			i += n;
			if(fullrune(buf, i))
				break;
		}
		buf[i] = 0;
		l = chartorune(&r, buf);
		if(r == 0xfff7)
			break;
		if(r < 0x20)
			print("ctl-%c\n", '@' + r);
		else if(r == 0x7f)
			print("del\n");
		else
			print("%C\n", r);
		memmove(buf, buf + l, i - l);
		i = i - l;
	}
done:
	close(cfd);
	close(mfd);
	exits(nil);
}

Re: [9fans] rawon for /dev/cons

[Rudolf Sykora]

Hello,

thanks Eric for your answer!

So if I understand right the rio(1) man page is slightly wrong. Not
only /dev/consctl has to be open but also /dev/mouse so that really
all characters be passed through. Is there any reason for this? Why
isn't it just the way the man page describes? (And actually not only
the man page but also FJB's Introduction to Operating Systems
Abstractions, page 290 suggests the same.)

Further. Is it so that in both cooked and raw mode /dev/cons always
serves UTF runes?

Is there any means of seeing the scancodes themselves? Or some other
way of seeing when a key is pressed and released (e.g. a simple Alt
key)? (I guess that providing some simple kbmap could perhaps do this
[or not?] but even if, it'd be a global thing while one would desire
it work on per window basis...)

Thanks for any comments!!
Ruda

Re: [9fans] rawon for /dev/cons

[erik quanstrom]

> all characters be passed through. Is there any reason for this? Why
> isn't it just the way the man page describes? (And actually not only
> the man page but also FJB's Introduction to Operating Systems
> Abstractions, page 290 suggests the same.)

the manual page is in error.  please submit a patch.

> Further. Is it so that in both cooked and raw mode /dev/cons always
> serves UTF runes?

i'm sorry.  i misspoke.  the console gives you utf-8, not runes.
all programs use utf-8 in plan 9, except in the odd case of dealing
with data from foreign systems, such as email.

- erik