Re: disable appletouch when plugging in mouse

[Paul Collins <paul@briny.ondioline.org>]

Johannes Berg <johannes@sipsolutions.net> writes:

> Bah, as nice as the script is, it messes up the appletouch driver
> because the touchpad's values drift over time and if we disable it the
> driver won't know.

You could try opening the evdev and doing an exclusive grab (code
attached).  This definitely prevents the events from getting to
/dev/input/mice, but I don't know if it'll stop other fds on the same
evdev from getting them.

/* based on code posted to linux-kernel by Peter Osterlund */
/* pass it a /dev/input/eventN node */

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>
#include <errno.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>

/* From linux/include/linux/input.h */
struct input_event {
	struct timeval time;
	unsigned short type;
	unsigned short code;
	unsigned int value;
};

#define EVIOCGRAB _IOW('E', 0x90, int) /* Grab/Release device */

int main(int argc, char* argv[])
{
	int fd;

	if (argc != 2) {
		fprintf(stderr, "no device specified\n");
		exit(1);
	}

	if ((fd = open(argv[1], O_RDONLY)) < 0) {
		perror("open");
		exit(1);
	}

	if (ioctl(fd, EVIOCGRAB, 1) < 0) {
		perror("ioctl");
		exit(1);
	}

	for (;;) {
		struct input_event ev;
		read(fd, &ev, sizeof(ev));
	}

	close(fd);
	return 0;
} 

-- 
Paul Collins
Melbourne, Australia

Dag vijandelijk luchtschip de huismeester is dood