http://www.unet.univie.ac.at/aix/files/aixfiles/termios.h.htm explains many of
the ioctl constants.. I just figured most of them out last week when I wrote
the below program to turn off terminal echo in asm, in case anyone needs an
example.. Yes, I over-comment assembly, otherwise I spend forever trying to
figure out what I did later ;p And on a related keyboard note, the A20 gate
sucks..
test6.asm:
; for vim syntax highlighting, asmsyntax=nasm
BITS 32
%define TCGETA 0x5405 ; <asm/ioctls.h>
%define TCSETA 0x5406
%define ICANON 0000002q ; <bits/termios.h>
%define ECHO 0000010q
%define ECHOE 0000020q
%define ECHOK 0000040q
%define ECHONL 0000100q
%define STDIN_FILENO 0 ; <unistd.h>
%define BUFSIZE 1024
section .bss
buf resb BUFSIZE
old resb 2 ; save the old flags
tty resb 17 ; struct termio tty
section .text
global _start
_start:
xor eax, eax ; eax = 0
mov al, 54 ; sys_ioctl
xor ebx, ebx ; ebx = 0
mov ecx, TCGETA
lea edx, [tty] ; &tty
int 80h ; syscall
mov ax, [tty + 6]
mov [old], ax ; save value
; and ax, ~(ICANON | ECHO | ECHOE | ECHOK | ECHONL)
and ax, ~(ECHO | ECHOE | ECHOK | ECHONL)
mov [tty + 6], ax
xor eax, eax ; eax = 0
mov al, 54 ; sys_ioctl
xor ebx, ebx ; ebx = 0
mov ecx, TCSETA ; int request
lea edx, [tty] ; &tty
int 80h
xor eax, eax ; eax = 0
mov al, 3 ; sys_read
xor ebx, ebx ; ebx = 0
mov bl, STDIN_FILENO ; int fd
mov ecx, buf ; void *buf
mov edx, BUFSIZE ; size_t count
int 80h ; syscall
mov ax, [old] ; retrieve old value
mov [tty + 6], ax ; restore it
xor eax, eax ; eax = 0
mov al, 54 ; sys_ioctl
xor ebx, ebx ; ebx = 0
mov ecx, TCSETA ; int request
lea edx, [tty] ; &tty
int 80h ; syscall
xor eax, eax ; eax = 0
mov al, 1 ; sys_exit
xor ebx, ebx ; ebx = 0
int 80h ; syscall
Hope it helps,
Joshua Roys
> On Tuesday 21 December 2004 08:29, Richard Cooper wrote:
> > I just found this in the archive. No one else answered it, so I guess I
> > will. It's quite the pain to figure out really. I remember spending
> > hours if not days trying to learn enough C that I could figure it out from
> > the kernel source. I really hate C.
> >
> > > How can I read a key from the keyboard when the key is available?
> >
> > You have to call TCSETSW, which sadly is like the most undocumented IOCTL
> > ever...
> >
> > This code is copy & pasted out of my program Softer. The assembly syntax
> > is different, but I'm sure you can figure it out. It also makes the I/O
> > completely raw, meaning you'll receive 127 instead of 8 for backspace, and
> > you'll receive 13 instead of 10 for enter. This is more than you want if
> > you're just looking to read the characters as they are typed, but I don't
> > remember how I ever figured out the correct values to get it to do what I
> > wanted. However, if you also want scancodes, then this is exactly what
> > you want.
> >
> > First you need to save the current settings which are creating the line
> > buffering and other nonsense so that you can put them back when your
> > program is done.
> >
> > sys sys_ioctl, 0, TCGETS, old_termios
> >
> > This requires a little structure to save into...
> >
> > old_termios
> > .c_iflag resd 1
> > .c_oflag resd 1
> > .c_cflag resd 1
> > .c_lflag resd 1
> > .c_cc resb 19
> >
> > Then you call another function to set the new mode...
> >
> > sys sys_ioctl, 0, TCSETSW, new_termios
> >
> > And of course this requires another structure...
> >
> > new_termios
> > .c_iflag dd 0
> > .c_oflag dd ONLCR | OPOST
> > .c_cflag dd B38400 | CS8 | CREAD | HUPCL
> > .c_lflag dd 0
> > .c_cc db $0, $3, $1c, $7f, $15, $4, $0, $1
> > db $0, $11, $13, $1a, $0, $12, $f, $17
> > db $16, $0, $0
>
> Ok. What are the meaning of this constants?
> I suppose that with this type of ioctl function, I can have more
> control over the keyboard.. Where I can find the documentation of
> this constants?
>
>
> >
> > And finally when your program is finished you need to put things back like
> > they were...
> >
> > sys sys_ioctl, 0, TCSETSW, old_termios
> >
> > And those nice constants are:
> >
> > sys_ioctl = 54
> > TCGETS = 0x5401
> > TCSETSW = 0x5403
> > ONLCR | OPOST = 5
> > B38400 | CS8 | CREAD | HUPCL = 0x4BF
>
> Yes, very nice! Why have you choosen B38400 | CS8 | CREAD | HUPCL ?
> In an aonther example I found this: ICANON | ECHO | ISIG
>
> Thanks,
> HIToC
>
> --
> With regards,
>
>
> HIToC
> [EMAIL PROTECTED]
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