Newbie request - compiling with Xlib.h

[Henry Lenzi]

Hi *

I'm trying to follow the following tutorial for Xlib prpogramming:

http://users.actcom.co.il/~choo/lupg/tutorials/xlib-programming/xlib-programming.html#preface

However, I can't seem to compile the simple-drawing.c example. I keep getting


> cc simple-drawing.c  -o simple-drawing -L/usr/X11/lib -lX11
simple-drawing.c:7:22: X11/Xlib.h: No such file or directory

or

> cc simple-drawing.c -o simple-drawing -lX11
simple-drawing.c:7:22: X11/Xlib.h: No such file or directory

What's the right incantation for this?

TIA.
Henry