Info Catalog
grub: insmod
grub: Command-line and menu entry commands
grub: linux
16.3.37 keystatus
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-- Command: keystatus [--shift] [--ctrl] [--alt]
Return true if the Shift, Control, or Alt modifier keys are held
down, as requested by options. This is useful in scripting, to
allow some user control over behaviour without having to wait for a
keypress.
Checking key modifier status is only supported on some platforms.
If invoked without any options, the 'keystatus' command returns
true if and only if checking key modifier status is supported.