COMPAT_IBCS2(8) BSD System Manager's Manual COMPAT_IBCS2(8)NAMEcompat_ibcs2 — setup procedure for running iBCS2 binaries
DESCRIPTION
NetBSD supports running Intel Binary Compatibility Standard 2 (iBCS2)
binaries. This only applies to i386 systems for now. Binaries are sup‐
ported from SCO UNIX and other systems derived from AT&T System V
Release 3 UNIX. iBCS2 support is only well tested using SCO binaries.
XENIX binaries are also supported although not as well tested. SVR4
binaries are supported by the COMPAT_SVR4 option.
iBCS2 supports COFF, ELF, and x.out (XENIX) binary formats. Binaries
from SCO OpenServer (version 5.x) are the only ELF binaries that have
been tested. Most programs should work, but not ones that use or depend
on:
kernel internal data structures
STREAMS drivers (other than TCP/IP sockets)
local X displays (uses a STREAMS pipe)
virtual 8086 mode
The iBCS2 compatibility feature is active for kernels compiled with the
COMPAT_IBCS2 option enabled. If support for iBCS2 ELF executables is
desired, the EXEC_ELF32 option should be enabled in addition to
COMPAT_IBCS2.
Many COFF-format programs and most ELF-format programs are dynamically
linked. This means that you will also need the shared libraries that the
program depends on. Also, you will need to create a “shadow root” direc‐
tory for iBCS2 binaries on your NetBSD system. This directory is named
/emul/ibcs2. Any file operations done by iBCS2 programs run under NetBSD
will look in this directory first. So, if an iBCS2 program opens, for
example, /etc/passwd, NetBSD will first try to open
/emul/ibcs2/etc/passwd, and if that does not exist open the ‘real’
/etc/passwd file. It is recommended that you install iBCS2 packages that
include configuration files, etc. under /emul/ibcs2, to avoid naming con‐
flicts with possible NetBSD counterparts. Shared libraries should also
be installed in the shadow tree.
Generally, you will need to look for the shared libraries that iBCS2
binaries depend on only the first few times that you install an iBCS2
program on your NetBSD system. After a while, you will have a sufficient
set of iBCS2 shared libraries on your system to be able to run newly
imported iBCS2 binaries without any extra work.
Setting up shared libraries
How to get to know which shared libraries iBCS2 binaries need, and where
to get them? Depending on the file type of the executable, there are dif‐
ferent possibilities (when following these instructions: you will need to
be root on your NetBSD system to do the necessary installation steps).
COFF binaries You can simply copy all of the available shared libraries
since they are fairly small in size. The COFF shared
libraries are typically found in /shlib and can be
obtained from the following sources:
SCO UNIX version 3.x (aka ODT)
SCO UNIX version 5.x (aka OpenServer)
SCO UnixWare
Many versions of SVR4.2/x86
After copying the shared libraries, you should have at
least the following files on your system:
/emul/ibcs2/shlib/libc_s
/emul/ibcs2/shlib/libnsl_s
/emul/ibcs2/shlib/protlib_s
ELF binaries You can simply copy all of the available shared libraries
from the source system or distribution or use ldd(1) to
determine the libraries required by a specific binary.
After copying the shared libraries, you should have at
least the following files on your system:
/emul/ibcs2/usr/lib/libc.so.1
/emul/ibcs2/usr/lib/libcrypt.so
/emul/ibcs2/usr/lib/libndbm.so
/emul/ibcs2/usr/lib/libsocket.so.1
If you don't have access to a SCO system, you will need to get the extra
files you need from a SCO distribution. As of January 1998, SCO sells a
copy of SCO OpenServer (iBCS2) and/or SCO UnixWare (SVR4) for per‐
sonal/non-commercial use for only the cost of shipping (about $20US).
The distribution comes on an ISO9660-format CDROM which can be mounted
and used to copy the necessary files.
Run the following script to copy the basic set of files from a SCO dis‐
tribution directory mounted somewhere locally:
/usr/share/examples/emul/ibcs2/ibcs2-setup [directory]
You should now be set up for SCO binaries which only need standard shared
libs.
BUGS
The information about SCO distributions may become outdated.
Attempting to a use a nameserver on the local host does not currently
work due to an absurd shortcut taken by the iBCS2 network code (remember
that there are no kernel sockets).
16/32/64 bit offsets may not be handled correctly in all cases.
BSD February 8, 1998 BSD
