add_menu name onval offval pos
Before adding commands to menus we need to create the menus themselves. The
add_menu command does this. The menu name is the text to appear for
the menu button. If this includes spaces it must be enclosed in quotes or
curly brackets.
Onval and offval define the state masks for the enable and disable sets. Menus are always enabled whenever any of the items within them are enabled, even if the offval set defines otherwise. Menus are usually enabled at startup (onval == 1) and disabled during busy mode (offval == 2).
The pos argument may be either left or right. This requests
the position to place the menu. Each leftwards positioned menu is packed to
the right of the currently shown left menus. Hence the order in which menus
are defined controls the order in which they will appear. Similarly for
rightwards positioned menus.
So for example, the Gap4 main menus are defined as follows.
add_menu File 1 2 left add_menu Edit 1 2 left add_menu View 1 2 left add_menu Options 1 2 left add_menu Experiments 1 2 left add_menu Lists 1 2 left add_menu Assembly 1 2 left add_menu Help 1 0 right
If more than one add_menu command is present for the same menu name the latter of the two takes priority.