Re: Restarting Curses

[Tim Mooney]

In regard to: Restarting Curses, Nicholas Cole said (at 3:30pm on Sep 3, 2009):

> Dear Curses List,
>
> I have a strange problem.  I have code that can start up and close
> down curses making sure the terminal is reset.  But if I call it a
> second time, the terminal is not properly reset.  I'm using python,
> but I suspect it would be the same in C.  What might I be doing wrong?

It's been years and years since I've done any curses programming so I'm
a little rusty, but I do remember this hard-learned lesson: you only want
to call initscr() ONCE per program.

I'm sure others can correct me on this, but if you need to "shell out" of
your curses app for a while, you do want to call endwin().  When you're
ready to come back to your curses app, I believe just a
"refresh()/wrefresh()/doupdate()" will do what you need.  I used
refresh() and that worked perfectly for the curses-based menu system I was
modifying.

PS: Looking at the source code for the curses-based app I worked on, it's
been 14 years since I last did any real curses programming, yet I still
remember the initscr() lesson.  ;-)

Tim

> Python curses provides a wrapper function precisely for the purpose of
> setting up the terminal and then resetting it, and the same behaviour
> happens whether I use that or set up curses myself.
>
> Minimal code looks something like:
>
> #def wrapper(call_function):
> #       locale.setlocale(locale.LC_ALL, '')
> #       screen = curses.initscr()
> #       curses.noecho()
> #       curses.cbreak()
> #
> #       return_code = call_function(screen)
> #
> #       curses.nocbreak()
> #       curses.echo()
> #       curses.endwin()
>
> As I say, it seems to work the first time it is called, but not the
> second.  Any insights?

--
Tim Mooney                                  address@hidden
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