Q37205: Operator sizeof Returns Type size_t, Defined as unsigned int

Article: Q37205
Product(s): See article
Version(s): 5.00 5.10 | 5.10
Operating System(s): MS-DOS | OS/2
Keyword(s): ENDUSER | docerr | mspl13_c
Last Modified: 21-NOV-1988

The sizeof operator returns a value that is of type size_t. The
definition of size_t is implementation-dependent, according to the
ANSI standard. In Microsoft C, the size_t type is defined in STDEF.H
and in MALLOC.H as an unsigned int. This information is documented in
the "Microsoft C Optimizing Compiler Run-Time Library Reference" on
Pages 38 and 98.

To use sizeof on huge items, which can be larger than 64K, you will
need to use a typecast on the sizeof expression as follows:

   char huge a[95000];
   unsigned long sizea;

   sizea = (unsigned long) sizeof(a);

Note: the Index entry for "size_t type" lists Pages 38 and 97; it
should say Pages 38 and 98.

The "Microsoft C Optimizing Compiler Language Reference" manual
describes the sizeof operator on Pages 120-121, section 5.3.4, but
does not give the return type.

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