problems with extrn/public

Hello,
I'm trying to call some ASM code from C++ and it isn't working. I've checked through the forum and couldn't find the proper way of doing this. The C++ program calls the function StringLength from my asm library and then outputs the length of a (fixed) string.

The asm source looks like this (note that this is for linux - but it shouldn't matter):

Code:

;strlen.asm

format ELF
include "%mylib%/linux.inc"            ;just loads up proc/end macro, etc

public StringLength as "_StringLength"

proc StringLength,lpString
      enter
      push ebx
      mov ebx,[lpString]
      or eax,-1
@@:
      inc eax
      cmp byte [ebx+eax],0
      jne @B
      pop ebx
      return
endp

The C++ code looks like this:

Code:

//say.cpp

#include <iostream>

using namespace std;
extern "C" int StringLength (char *);

int main()
{

  char *OutputString = "This is the wrong string. You blew it.\n";

  printf("The string length is %d bytes.\n",StringLength(OutputString));
  return (0);
}

I compile fasm with a simple fasm strlen.asm and then compile the main proggy with g++ say.cpp strlen.o -o say. But I keep getting this from g++:

Quote:

: undefined reference to `StringLength'

I'm sure I'm using extern and public incorrectly, but I'm not sure what I'm missing. Any advice is much appreciated

Thanks
--Chorus