diff --git a/examples/Makefile b/examples/Makefile
index 46aa43532..c06cafdf2 100644
--- a/examples/Makefile
+++ b/examples/Makefile
@@ -1,6 +1,7 @@
 include ../makeinclude
 
-ALL = tabs-simple$(EXEEXT) \
+ALL = howto-add_fd-and-popen$(EXEEXT) \
+      tabs-simple$(EXEEXT) \
       tree-simple$(EXEEXT)
 
 # default target -- build everything
@@ -9,9 +10,6 @@ default: $(ALL)
 tabs-simple$(EXEEXT): tabs-simple.cxx
 	fltk-config --compile tabs-simple.cxx
 
-tree-simple$(EXEEXT): tree-simple.cxx
-	fltk-config --compile tree-simple.cxx
-
 # clean everything
 clean:
 	$(RM) $(ALL)
diff --git a/examples/howto-add_fd-and-popen.cxx b/examples/howto-add_fd-and-popen.cxx
new file mode 100644
index 000000000..5e125d84c
--- /dev/null
+++ b/examples/howto-add_fd-and-popen.cxx
@@ -0,0 +1,72 @@
+//
+// "$Id$"
+//
+//     How to use popen() and Fl::add_fd() - erco 10/04/04
+//     Originally from erco's cheat sheet, permission by author.
+//
+//     Shows how the interface can remain "alive" while external
+//     command is running and outputing occassional data. For instance,
+//     while the command is running, keyboard navigation works,
+//     text can be highlighted, and the interface can be resized.
+//
+// Copyright 1998-2010 by Bill Spitzak and others.
+//
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Library General Public
+// License as published by the Free Software Foundation; either
+// version 2 of the License, or (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Library General Public License for more details.
+//
+// You should have received a copy of the GNU Library General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+// USA.
+//
+// Please report all bugs and problems on the following page:
+//
+//     http://www.fltk.org/str.php
+//
+#include <stdio.h>
+#include <unistd.h>
+#include <FL/Fl.H>
+#include <FL/Fl_Window.H>
+#include <FL/Fl_Multi_Browser.H>
+
+#define PING_CMD "ping -i 2 -c 10 localhost"	// 'slow command' under unix
+
+// GLOBALS
+FILE *G_fp = NULL;
+
+// Handler for add_fd() -- called whenever the ping command outputs a new line of data
+void HandleFD(int fd, void *data) {
+  Fl_Multi_Browser *brow = (Fl_Multi_Browser*)data;
+  char s[1024];
+  if ( fgets(s, 1023, G_fp) == NULL ) {		// read the line of data
+    Fl::remove_fd(fileno(G_fp));		// command ended? disconnect callback
+    pclose(G_fp);				// close the descriptor
+    brow->add(""); brow->add("<<DONE>>");	// append msg indicating command finished
+    return;
+  }
+  brow->add(s);					// line of data read? append to widget
+}
+
+int main(int argc, char *argv[]) {
+  Fl_Window win(600,600);
+  Fl_Multi_Browser brow(10,10,580,580);
+  if ( ( G_fp = popen(PING_CMD, "r") ) == NULL ) {	// start the external unix command
+    perror("popen failed");
+    return(1);
+  }
+  Fl::add_fd(fileno(G_fp), HandleFD, (void*)&brow);	// setup a callback for the popen()ed descriptor
+  win.resizable(brow);
+  win.show(argc, argv);
+  return(Fl::run());
+}
+
+//
+// End of "$Id$".
+//
diff --git a/examples/tabs-simple.cxx b/examples/tabs-simple.cxx
index 9fae9b456..e7e446570 100644
--- a/examples/tabs-simple.cxx
+++ b/examples/tabs-simple.cxx
@@ -85,3 +85,7 @@ int main(int argc, char *argv[]) {
   win->show(argc, argv);
   return(Fl::run());
 }
+
+//
+// End of "$Id$".
+//