Path: utzoo!attcan!uunet!decwrl!shelby!portia.stanford.edu!news
From: volovich@dendrite.Stanford.EDU (Gene Volovich)
Newsgroups: comp.lang.fortran
Subject: Calling a C function from Fortran.
Message-ID: <1990Aug2.191231.11783@portia.Stanford.EDU>
Date: 2 Aug 90 19:12:31 GMT
Sender: news@portia.Stanford.EDU (USENET News System)
Organization: Stanford University
Lines: 26

I'm calling a C function from a FORTRAN program on an RT running AOS, and 
using the standard C compiler and f77.  I actually got this to run, but 
my question is this: why does there need to be an underscore after the name
of the C function I'm calling?  Here's my code:

Fortran code:   ... 
                I=VISIT(J)
                ...

C code:         int visit_(k)
                int *k;
                {
                  printf("%d \n",*k);
                  return (*k+1);
                }

I compiled the FORTRAN code, and the C code, and then used f77 to link
them into an executable file.  I've never heard of anyone having this 
problem, so it all seems very strange to me.  Thanks, and I hope I'm
not wasting bandwidth with a trivial problem.  
 
                               +-------------------------------------------
- Gene Volovich                |  "We are the music makers.
Academic Information Resources |   We are the dreamers of dreams."
Stanford University            |                              - Willy Wonka
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