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Date: Wed, 12 Mar 2008 08:59:23 -0700
From: Brian Dessent <brian AT dessent DOT net>
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Subject: Re: Bug: C-prog from Win dies in fork; gdb.exe also won't run
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Dave Korn wrote:

>   Now, who supposes you could work around the restriction by writing
> 
>   * (WORD *) 0x004000dc = POSIX_CUI;
> 
> just before calling NtSetInformation?

How are you going to fool the executive by poking around in the PE
header from userspace long after the process has initialized?  The
executive fundamentally knows which subsystem any given process is
running in because it created it and manages the low level process
table.  That's not to say that you couldn't install a kernel driver that
somehow munges bits of the executive's internal datastructures to allow
this, but sweet mother of sh*t do I not want to have the job of the
person responsible for maintaining *that*.

Brian

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