Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!usc!jarthur!nntp-server.caltech.edu!toddpw
From: toddpw@nntp-server.caltech.edu (Todd P. Whitesel)
Newsgroups: comp.sys.apple2
Subject: Re: Tech Questions about GS/OS (and some ramblings)
Message-ID: <1991Jan6.081825.20294@nntp-server.caltech.edu>
Date: 6 Jan 91 08:18:25 GMT
References: <1990Dec21.070632.18209@rbdc>
Distribution: usa
Organization: California Institute of Technology, Pasadena
Lines: 28

AABENSON@MTUS5.BITNET writes:

>They WERE talking about shell executables (EXE files).  And YES, they CAN be
>changed into filetype S16 and expected to work IF:
>       [1]  They weren't using any shell information (no shell calls).
>       [2]  They end with a QUIT call, and not via RTL.  Shells don't really
>             care either way, but GS/OS does when an S16 file exits.

Note that this is not always sufficient. Parts of the Orca/C stdio library
depend on the shell being present, and barf if you S16 them.

>By the way, the way parameters are passed from the shell is NOT automatic. The
>shell executable (EXE file) must REQUEST the information.

Not according to the Programmers' Intro to the GS. According to page 261,

	"As soon as a shell application is launched .... It should also
	check the X and Y registers for a pointer to the shell-identifier
	string and input line."

X & Y are 0 if GS/OS launched the application. The shell identifier is 8 bytes
ASCII (BYTEWRKS for APW/Orca) and is immediately followed by a null-terminated
ASCII string -- the input line with I/O redirection and piping removed.

It is finder messages to S16's that must be requested.

Todd Whitesel
toddpw @ tybalt.caltech.edu