[Coco] Major OS-9 discovery to enhance script file use.

[tim lindner]

Robert Gault <robert.gault at worldnet.att.net> wrote:

> (chd /h0/MVUE)</1

I tested something like this on stock OS9 Level 2. I modified the
startup file to have this at the end:

(chd sys) </1
echo Success!

After it was done I got my prompt and did a PWD, and found my current
directory really was /DD/SYS. But the echo command did not execute.

When shell runs the startup file (or any script) it forks a sub shell,
changing directories in that sub-shell will not effect the parent shell.
Period.

What you have found is a way to crash the sub shell, and exeucte the CHD
command in the parent shells process. I think it crashes becuase you are
trying to redirect the STDIN of a built in shell command.

> (display 1b 21)</1
 
This works becuase you dup STDOUT and assign it to STDIN. This works
around a bug in Select when STDIN is an RBF path. Note, this does not
crash the sub-shell.

-- 
tim lindner
tlindner at ix.netcom.com                                            Bright