### Link 32-bit and 16-bit Code (OS/2)

You can statically link between 32-bit and 16-bit code with the following restrictions:

- the `main` function must be 32-bit code
- you cannot make any calls to 16-bit library functions in the 16-bit code
- you must compile the 16-bit code with the /ND option (with a 16-bit compiler)

These restrictions do not apply when you dynamically link 32-bit code to 16-bit DLLs.

Specify the stack size for calls to 16-bit routines with the #pragma stack16 directive.

Call Between 32-bit and 16-bit Code

Summary of Compiler Options
Compiler Option for 16-bit Declarations