Re: Apple //e shell?

[dempson@actrix.gen.nz (David Empson)]

Bart <me2@nowhere.org> wrote:

> I have a //e with a Focus on it running PRODOS 8 2.0.3. every now and then
> (and I cannot get it to repeat consistently) it will drop into what looks like
> a shell when I type BYE.

You should be able to get it consistently, assuming you are typing BYE
while running BASIC.SYSTEM (Applesoft BASIC while booted ProDOS), and
you are always running the same version of PRODOS and BASIC.SYSTEM.

I wouldn't call it a "shell".  It is actually the default program
selector which is installed by ProDOS and invoked when a ProDOS
application uses the QUIT call.  (BASIC.SYSTEM does this when you use
the BYE command.)  If you quit from any ProDOS application (SYS file)
then you should get the same program selector.

There are actually two program selectors in ProDOS-8 1.9 and later: the
original one, which prompts you to type in a prefix and pathname for the
next application (yuck!) and the interactive one that lets you browse
through volumes and subdirectories and pick a file visually.

If you are running an Apple IIe with an 80-column card (or a IIgs or
IIc) then you get the interactive one.  A 40-column IIe (or a ][ or ][+)
gets the old "type in the details" program selector.

Third party applications can replace the program selector with their own
code.  For example, AppleWorks 3.0 and later installs a program selector
called Birds Better Bye, which is similar in function to the newer
ProDOS selector, but it works in 40-column mode and supports older
machines.

I co-wrote a program called QUITTER (or QUITTER.SYSTEM) which installs
my own enhanced version of Birds Better Bye, adding a few more key
commands and the ability to display twice as many files (two columns
instead of one).

If you go right back to early versions of ProDOS (1.0.x) then the
program selector may be missing.  BASIC.SYSTEM 1.0 doesn't have a BYE
command, and the utility programs that came with the earliest system
software (FILER and CONVERT) don't actually use the QUIT call: they have
their own code to prompt you for another application to launch, which is
similar to the original quit code.

-- 
David Empson
dempson@actrix.gen.nz
Snail mail: P O Box 27-103, Wellington, New Zealand