Wait for X11 until ready

wait_for_x11.c

/* Compile:
       gcc -o wait_for_x11 wait_for_x11.c -lX11
  Run:
      ./wait_for_x11 :0
*/
#include <X11/Xlib.h>
#include <unistd.h>

int main(int argc, char *argv[]){
    Display *dpy;
    char *name = NULL;
    if (argc > 1){
        name = argv[1];
    }
    while(!(dpy=XOpenDisplay(name))){
        sleep(0.3);
    }
    return 0;
}