Re: curses vs. xterm key mismatch

[Will Parsons]

Thomas Dickey wrote:
> On Fri, 13 Apr 2007, Will Parsons wrote:
> 
>> I'm working on a curses application that is supposed to react to an End
>> key, but this does not seem to be recognized in a xterm under FreeBSD 6.1.
>> Investigation shows that when I press either of the End keys, what curses
>> sees is 0601, which seems to be defined as KEY_SELECT in curses.h.  (There
>> is no problem running under a real console.)  Is this an xterm issue, a
>> terminfo issue on FreeBSD, or something else, and what is the best/proper
> 
> It's a limitation of the way any version of curses works.
> 
> They use the first keycode in their table which is assigned to a given 
> string.  Since xterm is emulating a vt100/vt220, that means it's thinking
> of KEY_SELECT rather than the PC-style Home/End.  You can switch the
> terminal description and get a different behavior.

Thank you for your explanation but I'm still a bit confused.  Does that
mean that when I hit the End key on a PC keyboard, that sends the same
escape sequence as would a Select key on a real vt100, so that what I am
seeing is in a sense legitimate?  I don't quite understand what you mean by
"switch the terminal description" - is this something specific to FreeBSD
that I would have to ask on a FreeBSD newsgroup?

> A quick check shows I'm using the PC-style in xterm's terminfo.
> Ditto for ncurses.  FreeBSD has its own termcap (though I recall
> its xterm entries being modified to match ncurses a couple of years
> ago).  But it could be either flavor - or both.  At one point both
> definitions were in the terminal description, but since curses uses
> only one, I removed the one that was less useful.  If your terminal
> description has both, curses will use the first one in the table,
> (looks like KEY_HOME would override...)
> 
>> way of handling this?  (Obviously, I can have my program simply look for
>> KEY_SELECT in addition to KEY_END, but this doesn't seem right to me.)

I'm still unsure of what I should be doing - complaining to FreeBSD that
something is wrong with their termcap/terminfo, making some sort of
adjustment in my environment, or simply accepting that KEY_SELECT may do
the same as KEY_END and allowing for that in my application?

- Will