urgent.c

/* 
 * A simple example of setting the XUrgencyHint on an xterm from a program
 * running in it. Compile with:
 * 
 *     gcc -L/usr/X11R6/lib -lX11 urgent.c -o urgent
 * 
 */

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

static int set_urgency(Display *dpy, Window id, int set)
{
    XWMHints *hints = XGetWMHints(dpy, id);

    if(hints == NULL)
        return 0;

    if(set)
        hints->flags|=XUrgencyHint;
    else
        hints->flags&=~XUrgencyHint;

    return XSetWMHints(dpy, id, hints);
}

int main(void)
{
    Display *dpy;
    const char *ids;
    Window id;

    ids = getenv("WINDOWID");

    if(ids == NULL)
    {
       fprintf(stderr, "WINDOWID not set.");
       return EXIT_FAILURE;
    }

    id = atoi(ids);

    dpy = XOpenDisplay(NULL);

    if(dpy == NULL)
    {
        fprintf(stderr, "Unable to open display.");
        return EXIT_FAILURE;
    }

    /* Set the flag */
    if(!set_urgency(dpy, id, 1))
    {
        XCloseDisplay(dpy);
        fprintf(stderr, "Unable to set urgency.");
        return EXIT_FAILURE;
    }
    XFlush(dpy);

    getchar();
    
    /* Unset the flag */
    if(!set_urgency(dpy, id, 0))
    {
        XCloseDisplay(dpy);
        fprintf(stderr, "Unable to unset urgency.");
        return EXIT_FAILURE;
    }
    XFlush(dpy);

    XCloseDisplay(dpy);

    return EXIT_SUCCESS;
}