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Q44923: MASM Calling C Making MASM Main Routine

Article: Q44923
Product(s): See article
Version(s): 5.10
Operating System(s): MS-DOS
Keyword(s): ENDUSER | | mspl13_masm
Last Modified: 30-AUG-1989

You can make a program that starts with MASM and calls C. This method
of programming is not recommended because starting with MASM will
mean that the C start-up code will not be executed, which may cause
future problems calling some of the C library functions. Run-time
error messages may be affected as well as routines that use system
symbols.

The following is an example of the macro-assembler main routine
which calls a C routine.

        .MODEL LARGE,C
        .CODE
        EXTRN CSUB
MAIN    PROC           ; Must call main (_main without ,C)
        PUSH     AX             ; Push argument on stack
        PUSH     BX             ; Push another argument
        CALL     CSUB   ; Call C subroutine
        ADD   SP,4      ; Fix-up stack after C subroutine
MAIN ENDP
        END            ; Do not specify starting location

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