Gpc <unresolved symbol Assign>

Hi, I am having trouble resolving the symbol Assign in my pascal programs. I have no problems compiling and running under Borland, but I do not have dos based machines at my disposal and would like to compile under either gpc or xlp. Is there some library i need to tell it to link? If anyone have an answer for me, would you please reply via e-mail, since I am not a subscriber of this group. Thanks, -Jim