Unresolved external in BC 5.01

I'm trying to convert a 16-bit dll to 32-bit. The dll uses an ojbect file that I created using MASM 6.11c. I compiled the ASM file and have a new 32-bit .OBJ file. It compiled with no errors. The relevent part of the ASM file follows:

.model flat, stdcall      

In the header file for the dll, I have the following line to define the prototype for M250:

extern "C"
  BOOL __stdcall M250(short *command, long *response, short

The TargetExpert options are Platform:Win32 and Target Model: Console.

And the IDE project looks like this:

250dll32 {.dll]
   250dlld [.cpp]
   |--250dll [.h]
   M250_32  [.obj]
   default  [.def]

When I attempt to build the dll. I get the following message

Info :Building...
Info :Compiling C:\Model250\250ewin\version5\32bit\250dlld.cpp
Info :Linking C:\Model250\250ewin\version5\32bit\250dll32.dll
Warn :  Warning: .DEF file heap reserve size < 64K; 1MB default will be used
Warn :  Warning: .DEF file stack reserve size < 64K; 1MB default will be used
Error:  Error: Unresolved external 'M250' referenced from module 250dlld.cpp

What am I doing wrong? The project compiles and runs fine when I built it for 16-bit.
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Drop the NEAR....


Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
SeanRAuthor Commented:
I dropped the NEAR. No change, still unresolved external 'M250'.
Opps, I answer so many of these sometimes I forget and submit an incomplete answer. Sorry about that {:-)
In Win32 a short is two bytes and a long is four The compiler is trying to resolve a M250 with a short int, a long and another short int as arguments. You function has DWORD,DWORD,DWORD.
Adjust one or the other to match and this should go away (the key work here is should...)
If not, let me know...

Happy linkin'
Cloud Class® Course: MCSA MCSE Windows Server 2012

This course teaches how to install and configure Windows Server 2012 R2.  It is the first step on your path to becoming a Microsoft Certified Solutions Expert (MCSE).

Any by the way... pointers (like those your function uses) are 32 bit addresses (that 4 bytes to you and me) so try changing the prototype to
M250(DWORD command, DWORD response, DWORD *errorCode);
and see if it resolves. If so the problem is definitely in the declaration.

That declaration should end with DWORD errorCode);
DWORD *errorCode);
Sorry, too much tube time...

One final suggestion...
I typically use WINAPI (the same as FAR PASCAL) for exported DLL functions in Win32. I don't *think* this is the problem but if the above suggestions fail, try it.

SeanRAuthor Commented:
Sorry for the delay, I've been working on another project.
I have tried the suggestions given above, and I still get "unresolved external 'M250'". Could someone give me an example of a MASM assembly function that takes three arguments by reference in 32-bit code, and the calling declaration in C for Borland C++ 5.01?
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Microsoft Development

From novice to tech pro — start learning today.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.