Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!microsoft!kensy
From: kensy@microsoft.UUCP (Ken SYKES)
Newsgroups: comp.windows.ms
Subject: Re: .DLL files under Windows 3.0
Message-ID: <57434@microsoft.UUCP>
Date: 14 Sep 90 00:17:51 GMT
References: <90255.141800GOODWIN@MAINE.BITNET>
Reply-To: kensy@microsoft.UUCP (Ken SYKES)
Organization: Microsoft Corp., Redmond WA
Lines: 20

In article <90255.141800GOODWIN@MAINE.BITNET> GOODWIN@MAINE.BITNET (John A Potelle) writes:
>I know the .dll files are called Dynamic Link Libraries, but what
>are they used for ?


In a DOS program all functions that are external to the program are bound
at link time.  This implies that every .exe that uses a function will have
a copy of it in their .exe.  This is rather wateful.

In OS/2 and Windows functions can be placed in a DLL.  A program that uses
DLLs does not have a copy of the function in its .exe.  Instead it just
contains information on where to find the function when it needs it.  This
allows .exe files to be smaller.  Another advantage is only one copy of the
function needs to be in memory.

DLLs provide a more sensible way to offer common functionality than statically
linked libraries.

Ken Sykes
Disclaimer: The above opinions are solely my own.