Description of problem:
Creating a chrome less window of size equal to your screen resolution creates a
window of that size and covers the system task bar.
Version-Release number of selected component (if applicable):
// make a window chrome less
GtkWidget* window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
// set the size equal to screen resolution (1400 x 1050 in my case)
gtk_window_resize(GTK_WINDOW(window), 1400, 1050);
The window covers the whole desktop including the task bar.
The window should not cover the task bar, the WM should restrict the
window size to visible area
metacity has some code to auto-fullscreen windows that look like they were meant to be fullscreen; I'm guessing this is what you are hitting. Not going to deviate from Metacity upstream on this.
Creating chromeless windows that are most of the screen but not fullscreen is a bit of an unusual activity - it seems like the behavior would usually be unsatisfactory and confusing for the user. If you do want to do this, I'd suggest using the _NET_WORKAREA property on the root window"
to figure out an optimum size.