680x0:Opening a library
This is a example on how to open a library:
(with the Library Vector Offsets added so you won't need to use any includes yet)
OldOpenLibrary = -408 ; OldOpenLibrary(libName)(A1)
OpenLibrary = -552 ; OpenLibrary(libName,version)(A1,D0)
CloseLibrary = -414 ; CloseLibrary(library)(A1)
move.l $4.w,a6 ; Get the value at position $4 in memory ; This value is the base of exec.library
lea LibName(pc),a1 ; libName must be in A1 moveq #0,d0 ; version must be in D0 jsr OpenLibrary(a6) ; Call the OpenLibrary function
; OldOpenLibrary looks if the library is in memory (or ROM) ; and loads it if nessesary. ; Then it returns the base of graphics.library in d0
move.l d0,libbase ; Store the base
; Closelibrary needs the base of the library ; (the address given to you in D0 by OpenLibrary) ; to close the library
move.l libbase,a1 ; Get the base jsr CloseLibrary(a6)
rts
libname: dc.b 'dos.library',0 libbase: dc.l $00000000