[Oberon] Do Win-users have multi-file-editors too ?

J ö rg Straube joerg.straube at iaeth.ch
Sun Dec 6 10:46:42 MET 2009

> This thing's [I'm trying the smaller, 'wily' version of acme]
> configure/make,/compile..etc. C complex compiling system,
> shows errors in a source near:
> ] extern GC _getfillgc(Fcode, Bitmap*, unsigned long);
> ] extern GC _getcopygc(Fcode, Bitmap*, Bitmap*, int*);
> ] extern GC _getgc(Bitmap*, unsigned long, XGCValues *);
> Since I don't know C/C++, does this mean:
> call 3-arg function _getgc, which is "defined in an external module named
> GC"?   Would 'GC' be a system-module ?
> How do you see the system-module list ?

"extern" means that the function "_getgc" is defined somewhere else.
Later the C linker will find out where it gets that function from.
You can think of something like:
  FROM Somewhere IMPORT _getgc;

To compile this source, the C compiler needs the nbr and types of
arguments. So, C programmers need to define a prototype.
  GC _getgc (Bitmap*, unsigned long, XGCValues*)
  PROCEDURE _getgc(VAR Bitmap, LONGINT, VAR XGCValues): GC;


More information about the Oberon mailing list