Mx Using Script in input files

Dear colleagues, 

My predecessor on this project used input file commands like these: 

script,save as dwg D:\scm_ma40.dwg
999

I don't know the script command, and the manual information doesn't 'give me any clues. One would think this will produce a dwg conversion file in D:'s root, but it doesn't. Any insights are greatly appreiciated.