glutSetWindow -- sets the current window; glutGetWindow - returns the identifier of the current window.
void glutSetWindow (int win); int glutGetWindow (void);
glutSetWindow sets the current window; glutGetWindow returns the iden- tifier of the current window. If no windows exist or the previously current window was destroyed, glutGetWindow returns zero. glutSetWin- dow does not change the layer in use for the window; this is done using glutUseLayer.