🚀 go-pugleaf

Allan Pratt reports:
> I have investigated the alleged use of _shell_p by the AES and
> the Mark Williams shell, and I can't see that either of them uses this
> variable.

It's not surprising that none of these programs access location
0x4f6.  However, they obviously do use the string that is pointed
to by that location.  There are probably other pointers to it floating
around as well.  I think the Mark Williams shell receives this string
as its environment string when it is invoked, so it presumably
accesses it through its basepage.  To find out how the basepage
gets set and why, you'll have to look at the DESKTOP and/or the
code for Pexec.  Perhaps the DESKTOP passes the value of _shell_p
to Pexec when you double click on a .PRG file.  Or perhaps the desktop
supplies a 0 to Pexec, and Pexec simply passes on the DESKTOP's
own environment string, which it in turn probably gets from GEMBOOT.

Hope this helps.

--Mike Fischer  
    Arpanet:  <fischer@yale.arpa>
    UUCP:     <imagen!yale!fischer>
    Bitnet:   <fischer@yalecs>
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