This file is not FVWM configuration file. It is written Subpanel Settings, or manually with editor, and read by the /usr/local/libexec/nscde/keymenu command which will generate infostore variables with descriptive keyboard shortcut names which are used in NsCDE menus from NsCDE-Menus.conf and NsCDE-Functions.conf, and additionaly, use the whole line after the keyword in the first column with "Silent Key" prefix to dinamically generate this part of keybindings which are separated from NsCDE-Keybindings.conf and processed specially because they definition must automatically match keyboard binding description in various menus.

The syntax of this file is simple: first column is the keyword which becomes infostore variable (km_xrefresh as $[infostore.km_xrefresh]), and the rest columns of every line is FVWM "Key" sintax which is paired with "Silent Key" prefix during initialization with f_KeyMenu -a from NsCDE-Main.conf.

Every line, or dynamic keybinding can be overriden here if (re)defined in user's $FVWM_USERDIR/Keymeu.actions: whole file or just choosen keybindings. The goal is to get their descriptions (after functions and menus reload) automatically in place on menus. For example, "F3 A M" configuration for FVWM "Key" will become Alt+F3 description right of the (De)Shade item on titlebar left button popdown menu.

File Keymenu.actions is processed by /usr/local/libexec/nscde/keymenu script. This script generates FVWM infostore variables used in menus, and executes FVWM "Key" commands producing dynamic keybindings which are described in menus.

For a list of keybindings that are "dynamic", that is, not defined in NsCDE-Keybindings.conf, but in Keymenu.actions, see notices in section about NsCDE-Keybindings.conf.