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From: hardin@hpindda.HP.COM (John Hardin)
Newsgroups: comp.lang.c++
Subject: Re: C++ masquerading as C ... How?
Message-ID: <6170012@hpindda.HP.COM>
Date: 8 Jan 90 18:25:39 GMT
References: <6170011@hpindda.HP.COM>
Organization: HP Information Networks, Cupertino, CA
Lines: 46

In answer to my question about how to make a C++ function masquerade
as C, I received several replies all saying that I should use the
'extern "C"' construct.  Though I was familiar with the use of this
construct to tell C++ to use C linkage when linking with functions
writen in C, I was not aware that it should be used to tell C++
to generate C function names to the linker for locally defined
procedures.

For those who asked me to post what I found out, I offer this
simple example (which I used to prove to myself that it works):

-----------------------> test.c <-----------------------

#include <stdio.h>

main ()
  {
  printf ("The length of 'abcd' is %d.\n", foo ("abcd"));
  }

-----------------------> test2.C <-----------------------

#include <string.h>

extern "C" int foo (char * str)
  {
  return (strlen (str));
  }

----------------------------------------------------------

I created the executable 'test' as follows:

    CC -c test2.C
    cc -c test.c
    CC -o test test.o test2.o

Indeed this did link properly and produced the output

    The length of 'abcd' is 4.

To those who were kind enough to set me straight, thank you!

John Hardin
hardin%hpindgh@hplabs.hp.com
----------