This is truly a hack. The idea is taken from the Linux ibcs2 emulator.
To use this feature, you must use the option,
options SPX_HACK
in your config.
Also, in /compat/ibcs2/dev, you must do:
lrwxr-xr-x 1 root wheel 9 Oct 15 22:20 X0R@ -> /dev/null
lrwxr-xr-x 1 root wheel 7 Oct 15 22:20 nfsd@ -> socksys
lrwxr-xr-x 1 root wheel 9 Oct 15 22:20 socksys@ -> /dev/null
crw-rw-rw- 1 root wheel 41, 1 Oct 15 22:14 spx
Do NOT use old socksys driver as that has been removed.
This hack needs /compat/ibcs2/dev/spx to be any device that does NOT
exist/configured (so the now non-existant spx major/minor works fine).
When an open() is called, the error ENXIO is checked and then the
path is checked. If spx open detected, then a unix socket is opened
to the hardcoded path "/tmp/.X11-unix/X0".
As the Linux hacker author mentioned, the real way would be to detect
the getmsg/putmsg through /dev/X0R and /dev/spx. Until this true
solution is implemented (if ever), I think this hack is important
enough to be put into the tree, even though I don't like it dirtying
up my clean code (which is what #ifdef SPX_HACK is for).
Add new files created for emulator.
Modify NetBSD import to work with FreeBSD and add new features and
code. The complete emulator is essentially a combination of work/code
implemented by Sean Eric Fagan, Soren Schmidt, Scott Bartram, and myself,
Steven Wallace.
Features of this new emulator system include:
o "clean" code, including strict prototyping.
o Auto-generation of ibcs2 system calls, xenix system calls, isc system
calls. Generation includes system tables, structure definitions,
and prototyping of function calls.
o ibcs2 emulator does not rely on any COMPAT_43 system calls.
o embedded socksys support
o ibcs2 msgsys, semsys, shmsys calls supported if supported in kernel
o alternate /emul/ibcs2 namespace searched first for files in ibcs2
system. Usefull to keep sysv libraries, binaries in /emul/ibcs2.
o many other finer details and functions fixed or implemented.
which is used as a basis for a more complete and cleaner ibcs2 emulator.
(snapshot about May 1995 with a few files from September 1995)
Some files and code from old emulator still remains.
New files, features, and changes have been implemented by myself,
which will be shown in following commits.