Re: Multiple instances of DLL in memory.

From: Peter Below (TeamB) (100113.1101_at_compuXXserve.com)
Date: 11/28/03 

Date: Fri, 28 Nov 2003 19:57:04 +0100

In article <3fc76f93@newsgroups.borland.com>, Ihor Bobak wrote:
> I created a dll which sets a global WH_SHELL hook,
> and .exe which uses this dll.
>
> This dll sends messages to a window in my .exe when
> the global hook procedure is called by some process.
>
> The problem is next: this dll is loaded for each process
> separately. Process Viewer shows 10 or more copies of my
> dll in memory (used by each process which called my
> hook procedure).
>
> I cannot understand why my dll is not loaded just once?
> I saw many examples (written on C++) which set the
> same hook in the same way, but their dll is loaded
> only once and used by many processes simultaneously.

A hook DLL is always loaded into each running process, regardless of
what it has been written in. The OS will share the code pages between
processes but not the data pages, unless they have been marked as
shared memory. The Delphi linker does not support this but VC++ does,
for example. 

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Peter Below (TeamB)  
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