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4/8/2010

This function allocates a block of task memory.

Syntax

LPVOID CoTaskMemAlloc(
  ULONG 
cb
); 

Parameters

cb

[in] Size, in bytes, of the memory block to be allocated.

Return Value

A pointer to the allocated memory block indicates success. NULL indicates insufficient memory.

Remarks

The initial contents of the returned memory block are undefined – there is no guarantee that the block has been initialized. The allocated block may be larger than cbbytes because of the space required for alignment and for maintenance information.

If cbis zero, CoTaskMemAllocallocates a zero-length item and returns a valid pointer to that item. If there is insufficient memory available, CoTaskMemAllocreturns NULL.

Applications should always check the return value from this method, even when requesting small amounts of memory, because there is no guarantee the memory will be allocated.

Passing into this function any invalid and, under some circumstances, NULL pointers result in unexpected termination of the application.

To determine whether the platform supports this function, see Determining Supported COM APIs.

Requirements

Header objbase.h
Library ole32.lib
Windows Embedded CE Windows CE 2.0 and later
Windows Mobile Windows Mobile Version 5.0 and later