reverseIncrementalSearch() function

Removes the char at 'pos'. Returns 1 if the line needs to be refreshed, 2 if not and 0 if nothing was removed

Insert 'ch' at position 'pos' Returns 1 if the line needs to be refreshed, 2 if not and 0 if nothing was inserted (no room)

Captures up to 'n' characters starting at 'pos' for the cut buffer. This replaces any existing characters in the cut buffer.

Removes up to 'n' characters at cursor position 'pos'. Returns 0 if no chars were removed or non-zero otherwise.

Inserts the characters (string) 'chars' at the cursor position 'pos'. Returns 0 if no chars were inserted or non-zero otherwise.

Returns the unicode character at the given offset, or -1 if none.