problems in interface

Hi, dear netters:
   I am a new user in GRASS. I have a problem in GRASS.
Does anyone knows how to excute GRASS command or scripts
in external? In the other word, I excute d.3d or d.rast
and so on not in "GRASS4.1>" prompt. I would write a
interface between GRASS & another exppert system.
Thanks in advance

| Hung-Yue Lin , Graduate student Email:hylin@ev004.ev.nctu.edu.tw
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