COMPAT_NETBSD32(8) BSD System Manager's Manual COMPAT_NETBSD32(8)NAME
compat_netbsd32 -- setup procedure for 32-bit compatibility on 64-bit platforms
DESCRIPTION
The compat_netbsd32 module allows NetBSD/sparc64 to run NetBSD/sparc executables, and NetBSD/amd64 to run NetBSD/i386 executables.
To use compat_netbsd32, one must either have COMPAT_NETBSD32 and EXEC_ELF32 in the kernel, or load the compat_netbsd32 and exec_netbsd32 ker-
nel modules.
Static executables typically need no additional setup. Dynamic binaries require the dynamic linker plus shared libraries. Most of these
files will need to be placed under /emul/netbsd32.
The easiest method of installing support for these is via the emulators/netbsd32_compat14, emulators/netbsd32_compat15, and
emulators/netbsd32_compat16 packages, provided in the NetBSD packages collection. These install 32-bit a.out and ELF compatibility
libraries, respectively. The details of what is actually necessary for correct operation are given below. This obviously is handled by the
emulator packages.
For a.out compatibility, /usr/libexec/ld.so from a 32-bit distribution is required to exist as /emul/netbsd32/usr/libexec/ld.so. For 32-bit
ELF compatibility, /usr/libexec/ld.elf_so needs to be in /emul/netbsd32/usr/libexec/ld.elf_so.
The shared libraries for a.out binaries do not live under the /emul/netbsd32 directory, but under the /emul/aout directory, where the a.out
dynamic linker will find them.
BUGS
A list of things which fail to work in compatibility mode should be here.
IPC is not well supported.
sysctl(3) is not well supported.
BSD March 11, 2006 BSD
Check Out this Related Man Page
COMPAT_SVR4(8) BSD System Manager's Manual COMPAT_SVR4(8)NAME
compat_svr4 -- setup procedure for running SVR4/iBCS2 binaries compat_svr4_32 -- setup procedure for running 32-bit SVR4/iBCS2 binaries
DESCRIPTION
NetBSD supports running SVR4/iBCS2 binaries. This code has been tested on i386 (with binaries from SCO OpenServer and XENIX), m68k (with
binaries from AMIX) and sparc (with binaries from Solaris) systems. Most programs should work, but not ones that use or depend on:
kernel internal data structures
the /proc filesystem
the ticotsord loopback RPC mechanism (NIS uses this)
sound and video interfaces
threads (ttsession uses threads)
the streams administrative driver
The SVR4 compatibility feature is active for kernels compiled with the COMPAT_SVR4 option enabled. Since support for ELF executables is
included only if the kernel is compiled with the EXEC_ELF32 or EXEC_ELF64 options enabled, kernels which include COMPAT_SVR4 should also typ-
ically include EXEC_ELF32 (for 32-bit ELF support) and/or EXEC_ELF64 (for 64-bit ELF support).
Another compatibility feature is COMPAT_SVR4_32, which allows the execution of 32-bit SVR4 binaries on a machine with a 64-bit kernel. This
requires EXEC_ELF32 and COMPAT_NETBSD32 options as well as COMPAT_SVR4. It is configured the same way as COMPAT_SVR4 but uses the
/emul/svr4_32 directory instead of /emul/svr4. But typically, /emul/svr4_32 can be made to point to /emul/svr4 if the operating system
donating the libraries has support for both 32-bit and 64-bit binaries.
Execution of 32-bit SVR4 binaries on a machine with a 32-bit kernel uses COMPAT_SVR4, not COMPAT_SVR4_32.
Most SVR4 programs are dynamically linked. This means that you will also need the shared libraries that the program depends on and the run-
time linker. Also, you will need to create a ``shadow root'' directory for SVR4 binaries on your NetBSD system. This directory is named
/emul/svr4. Any file operations done by SVR4 programs run under NetBSD will look in this directory first. So, if a SVR4 program opens, for
example, /etc/passwd, NetBSD will first try to open /emul/svr4/etc/passwd, and if that does not exist open the 'real' /etc/passwd file. It
is recommended that you install SVR4 packages that include configuration files, etc under /emul/svr4, to avoid naming conflicts with possible
NetBSD counterparts. Shared libraries should also be installed in the shadow tree.
The simplest way to set up your system for SVR4 binaries is:
1. Make the necessary directories:
(me@netbsd) mkdir -p /emul/svr4/{dev,etc}
(me@netbsd) mkdir -p /emul/svr4/usr/{bin,lib,ucblib}
(me@netbsd) mkdir -p /emul/svr4/usr/openwin/{bin,lib}
(me@netbsd) mkdir -p /emul/svr4/usr/dt/{bin,lib}
2. Copy files from an svr4 system:
(me@svr4) cd /usr/lib
(me@svr4) tar -cf - . |
rsh netbsd 'cd /emul/svr4/usr/lib && tar -xpf -'
(me@svr4) cd /usr/ucblib
(me@svr4) tar -cf - . |
rsh netbsd 'cd /emul/svr4/usr/ucblib && tar -xpf -'
If you are running openwindows:
(me@svr4) cd /usr/openwin/lib
(me@svr4) tar -cf - . |
rsh netbsd 'cd /emul/svr4/usr/openwin/lib && tar -xpf -'
(me@svr4) cd /usr/dt/lib
(me@svr4) tar -cf - . |
rsh netbsd 'cd /emul/svr4/usr/dt/lib && tar -xpf -'
3. You will also probably need the timezone files from your Solaris system, otherwise emulated binaries will run on UTC time.
(me@netbsd) mkdir -p /emul/svr4/usr/share/lib/zoneinfo
(me@netbsd) mkdir -p /emul/svr4/etc/default
(me@svr4) cd /usr/share/lib/zoneinfo
(me@solaris) tar -cf -. |
rsh netbsd 'cd /emul/svr4/usr/share/lib/zoneinfo &&
tar -xpf -'
(me@netbsd) echo TZ=US/Pacific > /emul/svr4/etc/default/init
4. Set up the configuration files and devices:
(me@netbsd) cd /usr/share/examples/emul/svr4/etc
(me@netbsd) cp netconfig nsswitch.conf /emul/svr4/etc
(me@netbsd) cp SVR4_MAKEDEV /emul/svr4/dev
(me@netbsd) cd /emul/svr4/dev && sh SVR4_MAKEDEV all
As the major number allocated for emulation of SVR4 devices may vary between NetBSD platforms, the SVR4_MAKEDEV script uses the uname(1)
command to determine the architecture the devices nodes are being created for; this can be overridden by setting the MACHINE environment
variable accordingly.
An alternative method is to mount a whole SVR4 partition in /emul/svr4 and then override with other mounts /emul/svr4/etc and /emul/svr4/dev.
BUGS
Many system calls are still not emulated. The streams emulation is incomplete (socketpair does not work yet).
Most SVR4 executables can not handle directory offset cookies > 32 bits. More recent ones, compiled for large file support (Solaris 2.6 and
up) can. With older programs, you will see the message ``svr4_getdents: dir offset too large for emulated program'' when this happens. Cur-
rently, this can only happen on NFS mounted filesystems, mounted from servers that return offsets with information in the upper 32 bits.
These errors should rarely happen, but can be avoided by mounting this filesystem with offset translation enabled. See the -X option to
mount_nfs(8). The -2 option to mount_nfs(8) will also have the desired effect, but is less preferable.
BSD April 19, 1999 BSD