Re: retrieving invocation arguments

[Bart Schaefer <schaefer@brasslantern.com>]

On Sep 17, 11:23am, Adam Spiers wrote:
}
} Currently I have
} 
}   restart () {
}       exec $SHELL "$SHELL_ARGS" "$@"
}   }
} 
} and I do
} 
}   export SHELL_ARGS="$@"
} 
} in my ~/.switch_shell (run from bash).

Ah.  Well, "$@" doesn't include the option switches even in bash, and
bash has the same behavior as zsh with respect to $0 and the first non-
option argument following a -c command.  Even if you did have the option
switches, you couldn't use them if $SHELL had changed from the original
shell.

Also, "$SHELL_ARGS" is going to be one argument where the original "$@"
may have had several.

And I should repeat the warning about `export SHELL_ARGS="$@"' -- "$@"
is an array with each element quoted, so what you've really written is

    export SHELL_ARGS="$1" "$2" "$3" ...

which is probably not what you meant.  Using "$@" works in bash because it
treats the arguments to `export' as if they were assignment expressions;
but in zsh that requires `setopt kshtypeset' (4.0.2 and later).

Anyway, it's very difficult to restart the shell exactly as it was invoked
unless you stash the arguments very early in .zshenv and have a cooperative
/etc/zshenv.  Probably the best thing would be along the lines of:

    restart_saveargs() {
	local x='(interactive|shinstdin|stdin)'
	local -a on off
	typeset -ga restart_args restart_options
	on=( ${(ok)options[(R)on]:#$~x} )
	off=( ${(ok)options[(R)off]:#$~x}} )
	restart_options=(
	    ${on:+-o} ${(j.-o .)=on}
	    ${off:++o} ${(j.+o .)=off}
	)
	restart_args=( "$@" )
    }
    restart() {
        emulate -L zsh
	if [[ $SHELL:t = zsh* ]]; then
	    exec $SHELL $restart_options $restart_args
	else
	    exec $SHELL $restart_args
	fi
    }
    restart_saveargs "$@"

And now that's probably more glorious detail than I should have included.

-- 
Bart Schaefer                                 Brass Lantern Enterprises
http://www.well.com/user/barts              http://www.brasslantern.com

Zsh: http://www.zsh.org | PHPerl Project: http://phperl.sourceforge.net