🚀 go-pugleaf

I'm having trouble passing functions as arguments from C To Fortran routines
running:
DEC OSF/1 [RT] V1.2 (Rev. 10); Thu Apr 01 12:10:49 MET DST 1993
DEC OSF/1 V1.2 Worksystem Software (Rev. 10)

e.g. The following gives a segmentation fault when the Fortran routine 'e_'
     is reached:
     [Works fine under Ultrix, haven't checked elsewhere.]

#include <stdio.h>
int f_();
int e_(int (*u)());

int c(){ return 1;}
int d (int (*u)()) { return u();}

main()
{
printf("d (c ) returns %d.\n",d (c ));
printf("d (f_) returns %d.\n",d (f_));

printf("e_(c ) returns %d.\n",e_(c ));
printf("e_(f_) returns %d.\n",e_(f_));
}

      integer function f()
      f = 2
      return
      end

      integer function e(u)
      integer u
      external u
      e=u()
      return
      end

Note that C is able to pass the address of Fortran function to itself, but
can't pass an address of a function to Fortran.

I've looked in Bookreader, but wasn't able to find,
e.g. a Fortran Programmers Guide,
which usually includes section on mixing C and Fortran.

I've tried double indirection for passing the routine, as it is on the Apollo,
but it didn't help.

thanks,
burkhard         burow@vxdesy.cern.ch