default process forms

["xiaolei zhang" <maths@21cn.com>]

hello:

        The Scsh Reference Manual said:

------------------------------------------------------------------------------------
The default case (prog arg1 ... argn) is also implicitly backquoted. That is, 
it is equivalent to:

    (begin (apply exec-path `(prog arg1 ... argn)))

-------------------------------------------------------------------------------------

   I had tried:

        1、(ls)
        2、(begin (apply exec-path `(ls)))
    3、(run (ls))

        1 fails, and 2,3 worked. But the reference manual saids 1 is equivalent 
to 2, why 1 fails? The error messages are:

----------------------------
Error: undefined variable
       ls
       (package user)
----------------------------

        thank you

　　　　　　　　xiaolei zhang
　　　　　　　　maths@21cn.com
　　　　　　　　　　2006-04-11