On 23/01/2024 08:52, phoebus phoebus wrote:
"Xterm 216" is unclear for me.> PuTTY documentation in 4.4.3 Changing the action of the function keys and keypad explain it by "In Xterm 216 mode, the unshifted function keys behave the same as Xterm R6 mode. But pressing a function key together with Shift or Alt or Ctrl generates a different sequence containing an extra numeric parameter of the form (1 for Shift) + (2 for Alt) + (4 for Ctrl) + 1. For F1-F4, the basic sequences like ESC OP become ESC [1;bitmapP and similar; for F5 and above, ESC[index~ becomes ESC[index;bitmap~.
Thanks. It seems it is supported by most terminal applications in Linux. However usually enough such keystrokes are grabbed for window manager and desktop environment hotkeys. In the case of POS it may be a kind of single-application kiosk with no WM and DE.
The small program described in the previous proposal could indeed be the intermediate filter.
So you can offer developers alternatives: to extend a combined terminal+SSH application like putty or to create a filter working with any terminal application.