UNIX porting problem solved with system call

[Tracy Tims]

A big problem when porting UNIX is the management of several different
flavours of files.  When compiling cross tools, for instance, one wants
some native include files, and some target include files.  When cross
compiling for the target machine, one needs cross executables and native
includes.

How difficult would it be to write a system call (splitroot) which would
allow the superuser to designate a root for execs, and a different root
for normal opens?  This would allow a port team to build a directory of
cross tools and includes for building them.  An exact copy of the target
machine distribution filesystem could them be built by running a shell
that resolved all normal opens to files in the target machine distribution
directory, and all execs to files in the cross tools directory.

One could create a standard, reliable cross environment, and a distribution
directory that would be EXACTLY what would run native on the target machine.
No more hacking of makefiles and programs to pick up the right includes.

Any comments?

	Tracy Tims	{linus,allegra,decvax}!watmath!hcr!hcrvax!tracy
			    {lbl-csa,utzoo,watmath}!hcr!hcrvax!tracy
			      Human Computing Resources Corporation
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