DOCUMENT:Q11910  06-MAY-2001  [masm]
TITLE   :PRB: SIZE Operator Value
PRODUCT :Microsoft Macro Assembler
PROD/VER::4.0,5.0,5.1,6.0
OPER/SYS:
KEYWORDS:

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

 - Microsoft Macro Assembler (MASM), versions 4.0, 5.0, 5.1, 6.0 
-------------------------------------------------------------------------------

SYMPTOMS
========

When trying to get the length of a text string, using the SIZE operator can
produce undesired results. In the example below, MSG_LEN is set to a value of 1,
but it seems it should be set to a value of 11:

      MSG DB 'Darth Vader'
      MSG_LEN EQU SIZE MSG

CAUSE
=====

The value of MSG_LEN should be 1. The SIZE operator is defined to be the LENGTH
* TYPE as stated in the documentation. The expression, LENGTH MSG, will be equal
to 1 (when applied to a data label, the LENGTH operator returns the number of
elements created by the DUP operator; otherwise it returns 1) and the
expression, TYPE MSG, will be equal to 1. Therefore, the variable MSG_LEN will
be equal to 1.

RESOLUTION
==========

In Macro Assembler version 6.0, the SIZEOF operator can be used to calulate the
total number of bytes allocated to a data item. In versions prior to 6.0, a
simple way to calculate the value you want is as follows:

      MSG DB 'Darth Vader'
      MSG_LEN EQU $-MSG

Additional query words: 4.00 5.00 5.10 6.00

======================================================================
Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM510 kbMASM600 kbMASM400 kbMASM500
Version           : :4.0,5.0,5.1,6.0

=============================================================================

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS
PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND.  MICROSOFT DISCLAIMS
ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  IN NO
EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR
ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL,
CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF
MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES.  SOME STATES DO NOT ALLOW THE EXCLUSION
OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES
SO THE FOREGOING LIMITATION MAY NOT APPLY.

Copyright Microsoft Corporation 2001.