Dear Sir

I want to know the the meaning of following codes.
What does that do?

 SET Confirm Off
 PUBLIC Code1, Ok, Vou_no1
 Vou_no1 = 0
 CLOSE All
 USE gin_reg
 SORT On Date To temp
 USE temp
 COPY To gin_reg
 CLOSE All
 USE In 0 gin_reg
 USE In 0 sallint Index sallint
 USE In 0 avlbook

Please help