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From: dillon@CORY.BERKELEY.EDU.UUCP
Newsgroups: mod.computers.68k
Subject: Re: forking around
Message-ID: <8703112147.AA23679@cory.Berkeley.EDU>
Date: Wed, 11-Mar-87 16:47:35 EST
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Posted: Wed Mar 11 16:47:35 1987
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	You cannot fork() in the UNIX sense of the word without an MMU
period.  There is no way for the system to know which variables contain
pointers, or even which address registers currenty contain pointers, and
thus without an MMU to map a COPY of the data and stack segments (assuming
the code segment is not self modifying)  to *exactly* the same address on 
the forked process, you simply cannot do it.

	Now, there is one possible solution, but it involves making ALL 
pointers relative to some segment, and also means a program must always make
references in one instruction (e.g. you cannot take the effective address of
something and then indirect through it).

	Something you could do, though is a combination fork+exec call.

				-Matt