It can. I've been using Caps Lock as Escape across Linux, FreeBSD, and OS X for 7 years now. The various gui interfaces to xmodmap even have an option to do the flip for you (at least in GNOME, Cinnamon, and KDE).
That's easy - what @Lio was talking about was having Caps Lock be a tap for <Esc> and then holding it with another key would be <C->. Is that what you're talking about? Karabiner can accomplish this on macOS, but I can't find a gconf/gsetting/xmodmap combination to do this on Linux. Caps Lock as Escape is easy. Caps Lock as Ctrl is easy. Caps Lock as both doesn't seem to be possible on Linux.
Am I wrong? Can you point me toward more info on this? I'd really appreciate it - I would so love to be able to use tap-for-escape in all readline contexts.
That's easy - what @Lio was talking about was having Caps Lock be a tap for <Esc> and then holding it with another key would be <C->. Is that what you're talking about? Karabiner can accomplish this on macOS, but I can't find a gconf/gsetting/xmodmap combination to do this on Linux. Caps Lock as Escape is easy. Caps Lock as Ctrl is easy. Caps Lock as both doesn't seem to be possible on Linux.
Am I wrong? Can you point me toward more info on this? I'd really appreciate it - I would so love to be able to use tap-for-escape in all readline contexts.