Re: Do 'fork' copies the "Code" Memory space?

From: Måns Rullgård (mru_at_kth.se)
Date: 01/26/04 

Date: Mon, 26 Jan 2004 11:19:13 +0100

mru@kth.se (Måns Rullgård) writes:

> Andrei Voropaev <avorop@mail.ru> writes:
>
>> Not really. There's no need to have 2 copies of DLL. I better say .so
>> library, since I don't know for sure about DLL. The code would be stored
>> in the same physical memory. But different processes may access that
>> code at different virtual addresses.
>
> This works only if the shared library uses position independent code.
> If it doesn't, all memory references in the code will have to be
> adjusted to point to the correct places. The library will have a
> relocation table listing all instructions using absolute addresses
> that need to be checked.

Note, not all dynamic linkers support this. 

-- 
Måns Rullgård
mru@kth.se

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