Q76504: Static Variables Declared in MASM Routines Called from C

Article: Q76504
Product(s): Microsoft Macro Assembler
Version(s): MS-DOS:5.0,5.10,6.0,6.0a,6.0b
Operating System(s): 
Keyword(s): 
Last Modified: 06-MAY-2001

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The information in this article applies to:

- Microsoft Macro Assembler (MASM), versions 5.0, 5.10, 6.0, 6.0a, 6.0b 
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SUMMARY
=======

The programs below demonstrate how a variable declared in a Microsoft Macro
Assembler (MASM) subprogram will keep its value between calls from a C main
program.

MORE INFORMATION
================

Link the two programs below with the following command:

  link cmain masmsub,,, /nod llibce;

Sample Code #1
--------------

  // Filename: CMAIN.C
  // Compile options needed: /c /AL

  #include <stdio.h>

  extern int far MasmSub () ;

  main ()
  {
     int i ;
     for (i = 1; i < 11; ++i)          // Call the MASM subprogram 10
     {                                 // times, and its return value
        printf ("%d\n", MasmSub()) ;   // will be incremented by 1 each
     }                                 // time.
  }

Sample Code #2
--------------

  ; Filename: MASMSUB.ASM
  ; Assemble options needed: /mx /ml

  .MODEL LARGE, C
  .DATA
     var DW 0        ; This variable will keeps its value between calls.
  .CODE
  PUBLIC MasmSub
  MasmSub PROC FAR
     INC var
     MOV AX, var     ; Since the function returns an int, C will get the
     RET             ; return value from AX.
  MasmSub ENDP
          END

Additional query words: kbinf 5.00 5.10 6.00

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Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM600 kbMASM500 kbMASM600a kbMASM600b
Version           : MS-DOS:5.0,5.10,6.0,6.0a,6.0b

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