Thanks Greg! These are fantastic pointers.

As for the if statement, I was referring to the first one, i.e.

if [ "x$SHLVL" != "x1" ]; then
...
fi

But I think this thread answers my question:
http://stackoverflow.com/questions/4511407/how-do-i-know-if-im-running-a-nested-shell

James





On Wed, Mar 13, 2013 at 4:57 PM, Greg Klanderman <gak@klanderman.net> wrote:

> >>>>> On March 13, 2013 James Jong <ribonucleico@gmail.com> wrote:
>
> > 1) What doest the if statement above test?
>
> whether the file is readable.  the loop loads all readable files
> matching the pattern /etc/profile.d/*.sh
>
> > 2) When I run a zsh script, how can I prevent it from running /etc/zshrc?
>
> zsh -f
>
> > 3) When I switch to zsh from tcsh on an interactive shell using exec zsh
> -l,
> > how I can I prevent it from running /etc/zprofile?
>
> I use "setopt norcs" in my .zshenv and then specifically load the
> files I want to load depending on whether the shell is a login shell,
> interactive, etc.  You could also use "setopt noglobalrcs" which only
> prevents loading the global (/etc/...) ones.  Note that without the
> "-f" command-line option, you cannot prevent loading /etc/zshenv
> (alternately /etc/zsh/zshenv on some systems).
>
> Greg
>