[Xpert]Hot corners

[Mike Schiraldi]

Some screensavers in the Win / Mac world let you set "hot corners" and "cold
corners", which respectively immediately activate the screen saver and
inhibit it.

I'm working on a program that lets you do this with X11. It almost
works. The problem is that it only notices if the corner belongs to the root
window -- if another window is covering the root, my program doesn't get
notified of the PointerMotion event. 

Since it's so tiny, i've attached it. I was wondering if anyone could take a
quick look. I imagine it would be a simple fix; but i've never programmed in
X before, and i'm sort of figuring it out as i go along by ripping apart
other programs.

Thanks

/* By Mike Schiraldi <[EMAIL PROTECTED]> */
/* Compile with -Wall -L/usr/X11R6/lib -lX11 */

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <X11/Xlib.h>
#include <X11/Xutil.h>

int
main(int argc, char **argv)
{
    Display *display;
    Screen *screen;
    Window root;
    int height;
    int width;
    int i;

    char * commands[4] = {NULL, NULL, NULL, NULL};

    if (argc < 2) {
    usage:
      fprintf (stderr, 
"Specify commands for, respectively, the northwest, northeast, southwest, and
southeast corners of the screen. Use - for no command. For example:
%s - 'script1.sh' 'script2.sh' -
will run script1.sh when the pointer is in the northeast corner and script2.sh
when it's in the southwest.

Written by Mike Schiraldi <[EMAIL PROTECTED]>\n", argv[0]);
      exit(1);
    }

    if (strcmp (argv[1], "-h") == 0) goto usage;
    if (strcmp (argv[1], "-help") == 0) goto usage;
    if (strcmp (argv[1], "--help") == 0) goto usage;
    if (strcmp (argv[1], "-v") == 0) goto usage;
    if (strcmp (argv[1], "-version") == 0) goto usage;
    if (strcmp (argv[1], "--version") == 0) goto usage;

    for (i = 1; i <= 4 && i < argc; i++) {
      if (strcmp (argv[i], "-") != 0) 
        commands[i - 1] = argv[i];
    }

    if ((display = XOpenDisplay(NULL)) == NULL) {
        fprintf(stderr, "%s: can't open %s\en", argv[0], XDisplayName(NULL));
        exit(1);
    }

    root = DefaultRootWindow (display);

    screen = XDefaultScreenOfDisplay(display);
    height = XHeightOfScreen(screen) - 1;
    width  = XWidthOfScreen(screen) - 1;

    XSelectInput (display, root, PointerMotionMask);
      
    while (1) {
      int x, y, rv;
      char * command;

      Window junk1, junk2;
      int junk3, junk4;
      unsigned int junk5;
      XEvent junk6;

      XNextEvent(display, &junk6);
      fprintf (stderr, "Pointer motion!\n");

      rv = XQueryPointer (display, root, &junk1, &junk2, &x, &y,
                          &junk3, &junk4, &junk5);
      if (!rv) {
        fprintf (stderr, "XQueryPointer failed. Send me an email about it.\n");
      }

      if (x == 0 && y == 0) {
        command = commands[0];
      } else if (x == width && y == 0) {
        command = commands[1];
      } else if (x == 0 && y == height) {
        command = commands[2];
      } else if (x == width && y == height) {
        command = commands[3];
      } else {
        command = NULL;
      }

      if (command) {
        fprintf (stderr, "Running %s\n", command);
      }
    }

    exit(1);
}