[Dev-C++] assembly code in c

[Ben M. <ili...@at...>]

Ok, so i have a dilemma. I want to link assembler code to my C program 
that will print a line pointed to by a char *. the function is defined 
in my program as: extern void print_string (char *); and the assembly 
code is:

_print_string proc near

    PUSH BP

    MOV BP,SP

    MOV AH,09h
    MOV DX,OFFSET [BP+4]
    INT 21h

    POP BP

    RETN

_print_string endp

can anyone tell me why this is failing? I am trying to get the address 
off of the stack and then use it to access the string. What is the 
appropriate way to do this?