[Coco] Major OS-9 discovery to enhance script file use.
robert.gault at worldnet.att.net
Sun Jan 8 18:39:06 EST 2006
You have found something there. I just ran procs before and after using
a ()</1 command and two extra shells were generated.
tim lindner wrote:
> Robert Gault <robert.gault at worldnet.att.net> wrote:
> 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.
> 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.
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