SUMMARY
=======

The GLOBEDIT sample demonstrates how to create a CEdit derived class that
uses a globally allocated memory segment instead of the application’s local
heap, thereby increasing the maximum contents of the edit control to the
full 64K.

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

Under Windows edit controls use the application’s local heap to store their
text data.  Unfortunately this can greatly limit their maximum capacity of
64K if the application uses a large portion of the local heap.  In order to
be able to utilize the entire 64K capability of the edit control it must
have its own segment.

Windows edit controls determine the local heap of the application by using
the instance handle of the application.  The instance handle of an 
application is just the data segment address (segment only).  Therefore
the edit control just uses the instance handle directly as the segment
selector for its memory allocations.

In order to get the edit control to have its own segment, PreCreateWindow
must be overridden in a CEdit derived class.  In this overridden member
function GlobalAlloc is called to allocate a portion of memory from the
global heap (the size is not important since the edit control will grow
the segment as necessary).  The handle returned from the GlobalAlloc is
locked andrder to get  

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