*_emul_path variables
change macros CHECK_ALT_{CREAT|EXIST} to use that, 'root' doesn't need
to be passed explicitly any more and *_CHECK_ALT_{CREAT|EXIST} are removed
change explicit emul_find() calls in probe functions to get the emulation
path from the checked exec switch entry's emulation
remove no longer needed header files
add e_flags and e_syscall to struct emul; these are unsed and empty for now
count is 0, wait for use count to drain before finishing the close.
This is necessary in order for multiple processes to safely share file
descriptor tables.
systems running a BSD-ish server. No dynamically linked executable support
(it requires weird execve() hacks...), nor any Mach trap support. But it
ran lots of statically linked binaries well enough for me to get bootstrapped.