semaphores sometomes have odd behaviour... just use the same mutexes and
semaphores as everywhere else.

responses.

This allows XTerm to pass on all functions it implements.

Please use xtrn/termtest going forward.

DSR Pn ! ~ x x x x ST

broken for some of them...

Have getpixel() regenerate the whole screen when called.

It's a hack, but since both Nelgin *and* Mortifis asked for it...
If a string variable is defined in the current command-shell, you may display
that variable's current value using this @-code. This does not work for integer
variables (do you need that too?) and does not work for any other Baja modules
that are executed (e.g. executed *from* a command shell).
Note that Baja, by defaults converts variables names to all-CAPS during the
"compilation" phase (unless the "baja -c" option is used), so you'll want to
either specify the variable name in ALL-CAPS or (if "baja -c" was used), match
the capitalization used in the .src file.

interactive.

getstr's insert mode (Ctrl-V) indicator and edit/line modes. Global Hot Keys
(e.g. Ctrl-T) would do weird stuff like return the cursor to the end of the
line or redraw the input string multiple times.
So as part of this fix:
- backspasce() now removed the last count characters from the save-line buffer
  (it is a destructive backspace afterall).
- outchar('\b') (a non-destructive backspace) adds the \b to the save-line buf
- restoreline() now always redraws the current insert/overwrite indicator in
  the upper right-most corner fo the screen
- insert_indicator() now uses functions that aren't line-saved.

An unrelated change included in this comment: center() now sends a CR before
the cursor movement and centered-text, for times when the current column is
*not* already at 0. Very useful for use with @-codes (e.g. display some pattern
or "graphics" and then center some text over it).

current column is > 0, it'll maintain that same margin on the right-edge of the
screen (shortening the fill length).
This allows you to create nice dynamic horizontal lines/dividers with margins.

states, and there's no other threads around to change those states.

The SDL wiki lists KMOD_MODE as AltGR... if that flag is flying in a
keypress, do not block text input.