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From: ferdie@coyote.datalog.com (fred jarvis)
Newsgroups: comp.windows.ms.programmer
Subject: How to best represent a list in Windows?
Message-ID: <e2BXZ1w163w@coyote.datalog.com>
Date: 5 Apr 91 09:25:46 GMT
Sender: bbs@coyote.datalog.com (Waffle System)
Organization: Datalog Consulting, Tucson, AZ
Lines: 21


    I want to use a list structure in a Windows application.
Typically, something like
        typedef struct {
           datatype *data;
           listnode *next;
        } listnode;
would be used, with each node dynamically allocated.
    But in Windows, you're supposed to use GlobalAlloc or LocalAlloc,
which return handles, not pointers, then using GlobalLock &
GlobalUnlock or LocalLock etc. to get the pointers for only as long
as you need access.
    If listnode contains handles, rather than pointers, each time a
node is referenced, calls to GlobalLock & ..Unlock (or LocalLock...)
must be made, which seems inefficient to me.
    I know LocalAlloc returns a pointer if called with the
LMEM_FIXED flag, but this is discouraged by the higher powers
(e.g. Petzold).  So what is the best approach to take (besides
going back to DOS) ?

    Fred Jarvis    ferdie@coyote.datalog.com