Hello,
After recent discussion on the port-amd64 mailing list and some bug fixes this
year, I would like to propose the new manpage below to document the working
compatibility with BSDi binaries under NetBSD on i386 and amd64.
An additional manpage covering the other 4.3-4.4 BSD derived binaries that work
on NetBSD under COMPAT_NOMID might also be helpful in the future. I would be
interested in continuing to work on compat documentation.
Thanks,
Dan Plassche
compat_bsdos(8) NetBSD System Manager's Manual compat_bsdos(8)
NAME
compat_bsdos -- binary compatibility for BSDi releases
DESCRIPTION
The COMPAT_NOMID kernel option provides compatibility with BSDi 1-3
a.out(5) binaries on NetBSD/i386 and NetBSD/amd64. The option is
included in the GENERIC kernel on i386, but needs to be enabled along
with EXEC_AOUT on amd64.
Null memory protection must be disabled with the sysctl(7) option
vm.user_va0_disable set to 0 for the binaries to run successfully.
BSD/OS 2.0+ binaries also require an ldconfig(8) configuration or a sym-
bolic link pointing to the /emul/bsdos/shlib directory to run outside of
a chroot.
BSD/OS 4.0 switched to elf binaries that do not run under the compatibil-
ity layers currently available on NetBSD.
SEE ALSO
options(4), a.out(5), elf(5), sysctl(7), compat_netbsd32(8)
HISTORY
BSD/OS (BSD/386) 1.0-1.1 was derived from 4.3BSD-Reno code in the Net/2
release.
BSD/OS 2.0 was based on 4.4BSD-Lite, but introduced new static shared
libraries compiled into binary objects under /shlib. The build system
included the shlicc command with the -Bstatic flag that allowed reverting
to the standard library archive format.
OpenBSD 2.2-4.7 included a different compatibility implementation under
the COMPAT_BSDOS kernel option.
BUGS
BSD/OS compatibility was broken on NetBSD 5-6.
BSD/OS added SPARC support with release 3.0, but the binaries are incor-
rectly recognized and fail as sunos executables on NetBSD/sparc and
NetBSD/sparc64.
NetBSD 9.0 August 27, 2020 NetBSD 9.0
Source:
.\"
.\"
.\" Copyright (c) 2020 The NetBSD Foundation, Inc.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Dan Plassche.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
.Dd August 27, 2020
.Dt compat_bsdos 8 amd64,i386,sparc,sparc64
.Os
.Sh NAME
.Nm compat_bsdos
.Nd binary compatibility for BSDi releases
.Sh DESCRIPTION
.Pp
The
.Cd COMPAT_NOMID
kernel option provides compatibility with BSDi 1-3
.Xr a.out 5
binaries on
.Tn Nx Ns /i386
and
.Tn Nx Ns /amd64 .
The option is included in the
.Li GENERIC
kernel on
.Em i386 ,
but needs to be enabled along with
.Cd EXEC_AOUT
on
.Em amd64 .
.Pp
Null memory protection must be disabled with the
.Xr sysctl 7
option
.Va vm.user_va0_disable
set to
.Li 0
for the binaries to run successfully.
.Pp
.Bsx 2.0+
binaries also require an
.Xr ldconfig 8
configuration or a symbolic link
pointing to the
.Pa /emul/bsdos/shlib
directory to run outside of a chroot.
.Pp
.Bsx 4.0
switched to elf binaries that do not run under the
compatibility layers currently available on
.Nx .
.Sh SEE ALSO
.Xr options 4 ,
.Xr a.out 5 ,
.Xr elf 5 ,
.Xr sysctl 7 ,
.Xr compat_netbsd32 8
.Sh HISTORY
.Pp
.Tn Bsx "(BSD/386)"
1.0-1.1 was derived from
.Bx 4.3 Reno
code in the
.Tn Net/2
release.
.Pp
.Bsx 2.0
was based on
.Bx 4.4 Lite ,
but introduced new static shared libraries
compiled into binary objects under
.Pa /shlib .
The build system included the
.Li shlicc
command with the
.Fl Bstatic
flag that allowed reverting to the standard
library archive format.
.Pp
.Ox 2.2-4.7
included a different compatibility implementation
under the
.Li COMPAT_BSDOS
kernel option.
.Sh BUGS
.Pp
.Bsx
compatibility was broken on
.Nx
5-6.
.Pp
.Bsx
added
.Tn SPARC
support with release 3.0,
but the binaries are incorrectly recognized
and fail as
.Li sunos
executables on
.Tn Nx Ns /sparc
and
.Tn Nx Ns /sparc64 .
