[Brian Elmegaard <be@me...>]

Hi,

I have been able to write gcc-code that uses the RefrigC.dll in 
http://www.et.dtu.dk/WinDali/Files/RefEqns_3.10.ZIP
This library code has been written in Delphi and it has been used from 
both the Salford and the MS fortran compilers. However both of these 
have extensions which makes it possible to specify which input types the 
dll functions expect.

C as well makes it possible to specify this as:
extern __int32 SetRNumber(char* ANum);
extern __int32 GetRNumber(char* ANum);
extern double PDewT(double T);
extern double TDewP(double P);
extern double  SDewT(double T);
extern __int32  TVSP(double S,double P,double* T,double* V);

With g77 I see no way to specify this and it seems that I have to 
specify it to use the dlls.

The following compiles and links but  outputs only rubbish when running 
the program:
      program refrig

      implicit none
      external SetRNumber
      external GetRNumber
      external PDewT
      external TDewP
      external SDewT
      external  TVSP
      double precision PDewT
      double precision TDewP
      double precision  SDewT
     
      character*200 AName
      double precision ps,ts,ss,vs,tsnew
 
      Call SetRNumber('R134a')
      call GetRNumber(AName)
      print*,'Refrigerant: ',AName
      print*,'-------------------------'
     
      ts = 273.15
      ps = PDewT(ts)
      ts = TDewP(ps)
     
      print*,'PDew [bar]   : ',ps/1E5
      print*,'TDew [C]     : ',ts-273.15
      print*,'-------------------------'
     
      ss = SDewT(ts)
      call TVSP(ss,ps,tsnew,vs)
 
      print*,'SS [kJ/kg]   : ',ss/1E3
      print*,'TSNew [C]    : ',tsnew-273.15
      print*,'PSNew [bar]  : ',ps/1E5
      print*,'VSNew [m^-3] : ',vs
      print*,' '
      end
 

Is there a way out or do I have to write a c-function to interface a dll 
from gcc?

Regards,
Brian