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Q39235: Declaring a Communal Variable of a Record Type

Article: Q39235
Product(s): Microsoft Macro Assembler
Version(s): 5.0,5.1,5.1a,6.0,6.0a,6.0b
Operating System(s): 
Keyword(s): 
Last Modified: 06-MAY-2001

-------------------------------------------------------------------------------
The information in this article applies to:

- Microsoft Macro Assembler (MASM), versions 5.0, 5.1, 5.1a, 6.0, 6.0a, 6.0b 
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SUMMARY
=======

In order to declare a communal variable of a record type, declare the variable
whose size matches the size of the record type. There is no need to specify that
the variable is of the record type.

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

The following sample program demonstrates this information:

Sample Code
-----------

  ;Assemble options needed: none

  ; module 1

          .model small
          DOSSEG

  EXTRN   proc2:proc
          .stack 100h

          .data
  color   RECORD   blink:1, back:3, intense:1, fore:3
          COMM     near pixel:byte     ; use "byte" because
                                       ; color has size byte.
          .code
  start:  MOV ax, @data
          MOV ds, ax

          MOV pixel, color <1,2,1,3> ; now the variable pixel
                                     ; should contain abh (1 010 1 011)
          CALL proc2
          MOV ax, 4c00h
          INT 21h

          END start

  ******************************
  ; module 2

          .model small
          DOSSEG

          .stack 100h

          .data
  color   RECORD   blink:1, back:3, intense:1, fore:3
          COMM     near pixel:byte

          .code
  PUBLIC  proc2

  proc2   PROC
          MOV ah, 0
          MOV ah, pixel  ; ah should contain abh (1 010 1 011)
          RET
  proc2   ENDP

          END

Additional query words: 5.00 5.10 5.10a 6.00 6.00a 6.00b

======================================================================
Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM510 kbMASM600 kbMASM500 kbMASM600a kbMASM510a kbMASM600b
Version           : :5.0,5.1,5.1a,6.0,6.0a,6.0b

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