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Date: Fri, 20 Jan 2006 11:58:36 +0000
From: Cliff Hones <cliff AT hones DOT org DOT uk>
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Subject: Re: Need information about data and bss segment address access in  cygwin
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Sudhahar wrote:
> Thanks Dave your reply answered the question where they declared. But
> how does these variables get the segment address of data and bss for a
> running process to make a copy to the child process? This is the
> questions which is a puzzle to me.

The linker places these variables at the start and end of the data and
bss segments.  The application can then find the addresses of the segments
by taking the address of the variables (eg &__data_start__).  They aren't
strictly variables in the C sense, inasmuch as trying to read or assign
to them may corrupt your application or cause a segmentation error.

Look in winsup/cygwin/lib/_cygwin_crt0_common.cc

-- Cliff

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