#!/usr/local/bin/octave -qf
#
# Example Octave program using the GTK-server
#
# Tested with Octave 2.1.72 and GTK-server 2.0.7
#	on Slackware Linux 10.2.
#
# January 2, 2006 - PvE.
#
#------------------------------------------------

# Communication function with GTK-server
function result = gtk (message)

    global pout;
    global pin;

    fputs(pout, message);
    result = fgetl(pin);

endfunction

#------------------------------------------------

# First, setup pipes
[readpipe, err, msg] = pipe ()
if (err != 0)
    printf("Can not create pipe!\n");
    exit(-1);
endif

[writepipe, err, msg] = pipe ()
if (err != 0)
    printf("Can not create pipe!\n");
    exit(-1);
endif

# Then fork
[pid, msg] = fork ()
if (pid < 0)
    printf("Can not FORK!\n");
    exit(-1);
endif

# Child process
if (pid == 0)

    # Close the parent pipes
    fclose(nth(writepipe,2));
    fclose(nth(readpipe,1));

    # Duplicate STDIN and STDOUT
    [fid, msg] = dup2 (nth(writepipe,1), stdin);
    fclose(nth(writepipe,1));

    [fid, msg] = dup2 (nth(readpipe,2), stdout);
    fclose(nth(readpipe,2));

    # Start GTK-server
    system("gtk-server -stdin");

# This is the parent process
else

    # Close the child pipes first
    fclose(nth(writepipe,1));
    fclose(nth(readpipe,2));

    # Get the active filehandles
    global pout = nth(writepipe,2);
    global pin = nth(readpipe,1);

    # Setup the GUI
    gtk("gtk_init NULL NULL");
    win = gtk("gtk_window_new 0");
    gtk(["gtk_window_set_title ", win, " \"Octave GTK-server demo with STDIN\""]);
    gtk(["gtk_window_set_default_size ", win, " 400 200"]);
    gtk(["gtk_window_set_position ", win, " 1"]);
    tbl = gtk("gtk_table_new 10 10 1");
    gtk(["gtk_container_add ", win, " ", tbl]);
    lbl = gtk("gtk_label_new \"Octave is compatible with all GTK versions now!\"");
    gtk(["gtk_table_attach_defaults ", tbl, " ", lbl, " 1 9 1 4"]);
    but = gtk("gtk_button_new_with_label \"Click to Quit\"");
    gtk(["gtk_table_attach_defaults ", tbl, " ", but, " 7 9 7 9"]);
    act = gtk("gtk_button_new_with_label \"Some action\"");
    gtk(["gtk_table_attach_defaults ", tbl, " ", act, " 2 4 7 9"]);
    gtk(["gtk_widget_show_all ", win]);
    
    event = "";

    while (!strcmp(event, win) && !strcmp(event, but))

	event = gtk("gtk_server_callback wait");

	if strcmp(event, act)
	    printf("Some action on the console!\n");
	endif
    endwhile

    gtk("gtk_server_exit");

endif