keyboard hook

Hello,
I'm trying to get a keyboard hook in X. My aim is to
get the time when some key was last pressed (I don't care what key).
How can I do it properly?

I found two ways:
--snip--
Window root,root2,windowIn,dummywin;
int rx,ry,wx,wy,screen;
unsigned int modifs;
int err;
screen=0;
root = XRootWindow(dd,screen);
XSelectInput(dd,root,KeyPressMask);

int rx2,ry2;
while(1)
{
char keys[33];;
XQueryKeymap(dd, keys);
int i;
for (i=0; i<32; i++) {
printf("%d ", keys[i]);
}
printf("\n");
}
--snip--

The "for" loop prints the keyboard state and works fine, but it requires probing
the keyboard all the time.

Another tried method was to read from /dev/input/... (keyboard).
But that one requires root privileges.


I want to write a program like xwrits so I have to know if user is doing something or not.
So any method that reveals that the user is active and he's typing/working would be helpful.

Regards
Michael

"news" <abuse@inetia.pl> wrote in message
news:et9stv$cd0$1@mx1.internetia.pl...[color=blue]
> Hello,
> I'm trying to get a keyboard hook in X. My aim is to
> get the time when some key was last pressed (I don't care what key). How
> can I do it properly?
>
> I found two ways:
> --snip--
> Window root,root2,windowIn,dummywin; int rx,ry,wx,wy,screen;
> unsigned int modifs;
> int err;
> screen=0;
> root = XRootWindow(dd,screen);
> XSelectInput(dd,root,KeyPressMask);
>
> int rx2,ry2;
> while(1) {
> char keys[33];;
> XQueryKeymap(dd, keys);
> int i;
> for (i=0; i<32; i++) {
> printf("%d ", keys[i]);
> }
> printf("\n");
> } --snip--
>
> The "for" loop prints the keyboard state and works fine, but it requires
> probing
> the keyboard all the time.
>
> Another tried method was to read from /dev/input/... (keyboard).
> But that one requires root privileges.
>
>
> I want to write a program like xwrits so I have to know if user is doing
> something or not.
> So any method that reveals that the user is active and he's typing/working
> would be helpful.
>[/color]

XSelectInput(...)

loop:
XtAppNextEvent(app, &event);
if ( event.type == KeyPress ) {
time = event.xkey.time;
}
XtDispatchEvent( &event );
endloop

Be sure to #include the appropriate header(s), and properly declare all
variables.
--
Fred L. Kleinschmidt
Boeing Associate Technical Fellow
Aero Stability and Controls Computing

>>[color=blue][color=green]
>> I want to write a program like xwrits so I have to know if user is doing
>> something or not.
>> So any method that reveals that the user is active and he's typing/working
>> would be helpful.
>>[/color]
>
> XSelectInput(...)
>
> loop:
> XtAppNextEvent(app, &event);
> if ( event.type == KeyPress ) {
> time = event.xkey.time;
> }
> XtDispatchEvent( &event );
> endloop
>
> Be sure to #include the appropriate header(s), and properly declare all
> variables.[/color]

Fred,
Thank you, but I believe I have tried a similar solution and it
reported only keypresses from my application, while I need to
know about keypresses from ALL applications. My program is to
run in the background and it needs to know that the user is
typing something somewhere.

Regards
Michael

OK, I have found a solution:

#include <X11/extensions/scrnsaver.h>

.....

while(1)
{

Time idleTime = 0; /* millisecs since last input event */

static XScreenSaverInfo* mitInfo = 0;
if (!mitInfo) mitInfo = XScreenSaverAllocInfo ();
XScreenSaverQueryInfo (dd, DefaultRootWindow (dd), mitInfo);
idleTime = mitInfo->idle;

printf("%d\n", idleTime/1000);
}

Regards
Michael

> I need to know about keypresses from ALL applications. My program is to[color=blue]
> run in the background and it needs to know that the user is typing
> something somewhere.[/color]

If you merely need to know IF the user is typing, not WHAT the user is
typing, have a look at any of the "screenblank" programs. They detect
keyboard and mouse activity and only activate after X minutes of
inactivity. (Maybe some hack involving /dev/console ?)
-WBE

On Mar 15, 11:23 pm, news <a...@inetia.pl> wrote:[color=blue]
> OK, I have found a solution:
>
> #include <X11/extensions/scrnsaver.h>
> ...[/color]

You could also use Record extension, it's very easy to use and gives
more information, e.g. in which window key was pressed.

--
Regards
Mariusz