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From: Lenik <lenik AT bodz DOT net>
Subject:  Re: Question of the necessity of rebaseall
Date:  Thu, 14 May 2009 09:05:34 +0800
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On 2009-5-14 8:55, Larry Hall (Cygwin) wrote:
> Lenik wrote:
>> Imagebase in PE header is something a bit of optional, that means if
>> two dlls with same imagebase, the OS kernel will automaticly relocate
>> one of them, to put them in different virtual spaces. So, rebase
>> should be a utility for optimizing the overall start-up speed, to
>> reduce avoidable relocations, rather then fix start-up errors.
>>
>> Any idea?
>
> cygwin1.dll cannot be relocated if the fork semantics are to work. So
> while what you say above is true for apps in general, it's not true for
> Cygwin apps.
>

I can't figure out how fork will break the relocation, for libraries 
have been loaded, they're already relocated before invoke into fork, and 
for libraries haven't been loaded, they don't need to share memory after 
new processes created by fork.


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