COMPAT_FREEBSD(8)       NetBSD System Manager's Manual       COMPAT_FREEBSD(8)

NAME
     compat_freebsd -- setup procedure for running FreeBSD binaries

DESCRIPTION
     NetBSD supports running FreeBSD binaries.  Most binaries should work,
     except programs that use FreeBSD-specific features.  These include
     i386-specific calls, such as syscons utilities.  The FreeBSD compatibil-
     ity feature is active for kernels compiled with the COMPAT_FREEBSD option
     enabled.

     A lot of programs are dynamically linked. This means, that you will also
     need the FreeBSD shared libraries that the program depends on, and the
     runtime linker.  Also, you will need to create a ``shadow root'' direc-
     tory for FreeBSD binaries on your NetBSD system. This directory is named
     /emul/freebsd.  Any file operations done by FreeBSD programs run under
     NetBSD will look in this directory first.  So, if a FreeBSD program
     opens, for example, /etc/passwd, NetBSD will first try to open
     /emul/freebsd/etc/passwd, and if that does not exist open the `real'
     /etc/passwd file.  It is recommended that you install FreeBSD packages
     that include configuration files, etc under /emul/freebsd, to avoid nam-
     ing conflicts 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 FreeBSD
     binaries depend on only the first few times that you install a FreeBSD
     program on your NetBSD system. After a while, you will have a sufficient
     set of FreeBSD shared libraries on your system to be able to run newly
     imported FreeBSD binaries without any extra work.

   Setting up shared libraries
     How to get to know which shared libraries FreeBSD binaries need, and
     where to get them? Basically, there are 2 possibilities (when following
     these instructions: you will need to be root on your NetBSD system to do
     the necessary installation steps).

     1.   You have access to a FreeBSD system.  In this case you can temporar-
          ily install the binary there, see what shared libraries it needs,
          and copy them to your NetBSD system.  Example: you have just ftp-ed
          the FreeBSD binary of SimCity.  Put it on the FreeBSD system you
          have access to, and check which shared libraries it needs by running
          `ldd sim':

                me@freebsd% ldd /usr/local/lib/SimCity/res/sim
                     /usr/local/lib/SimCity/res/sim:
                          -lXext.6 => /usr/X11R6/lib/libXext.so.6.0 (0x100c1000)
                          -lX11.6 => /usr/X11R6/lib/libX11.so.6.0 (0x100c9000)
                          -lc.2 => /usr/lib/libc.so.2.1 (0x10144000)
                          -lm.2 => /usr/lib/libm.so.2.0 (0x101a7000)
                          -lgcc.261 => /usr/lib/libgcc.so.261.0 (0x101bf000)

          You would need go get all the files from the last column, and put
          them under /emul/freebsd.  This means you eventually have these
          files on your NetBSD system:
          /emul/freebsd/usr/X11R6/lib/libXext.so.6.0
          /emul/freebsd/usr/X11R6/lib/libX11.so.6.0
          /emul/freebsd/usr/lib/libc.so.2.1
          /emul/freebsd/usr/lib/libm.so.2.0
          /emul/freebsd/usr/lib/libgcc.so.261.0

          Note that if you already have a FreeBSD shared library with a match-
          ing major revision number to the first column of the ldd output, you
          won't need to copy the file named in the last column to your system,
          the one you already have should work.  It is advisable to copy the
          shared library anyway if it is a newer version, though.  You can
          remove the old one.  So, if you have these libraries on your system:
          /emul/freebsd/usr/lib/libc.so.2.0

          and you find that the ldd output for a new binary you want to
          install is:

          -lc.2 => /usr/lib/libc.so.2.1 (0x10144000)

          You won't need to worry about copying /usr/lib/libc.so.2.1 too,
          because the program should work fine with the slightly older ver-
          sion.  You can decide to replace the libc.so anyway, and that should
          leave you with:
          /emul/freebsd/usr/lib/libc.so.2.1

          Finally, you must make sure that you have the FreeBSD runtime linker
          and its config files on your system.  You should copy these files
          from the FreeBSD system to their appropriate place on your NetBSD
          system (in the /emul/freebsd tree):
          usr/libexec/ld.so
          var/run/ld.so.hints
     2.   You don't have access to a FreeBSD system. In that case, you should
          get the extra files you need from various ftp sites.  Information on
          where to look for the various files is appended below. For now,
          let's assume you know where to get the files.

          Retrieve the following files (from _one_ ftp site to avoid any ver-
          sion mismatches), and install them under /emul/freebsd (i.e.
          foo/bar is installed as /emul/freebsd/foo/bar):
          sbin/ldconfig
          usr/bin/ldd
          usr/lib/libc.so.x.y.z
          usr/libexec/ld.so

          ldconfig and ldd don't necessarily need to be under /emul/freebsd,
          you can install them elsewhere in the system too. Just make sure
          they don't conflict with their NetBSD counterparts.  A good idea
          would be to install them in /usr/local/bin as ldconfig-freebsd and
          ldd-freebsd.

          Run the FreeBSD ldconfig program with directory arguments in which
          the FreeBSD runtime linker should look for shared libs.  /usr/lib
          are standard, you could run like the following:

                me@netbsd% mkdir -p /emul/freebsd/var/run
                me@netbsd% touch /emul/freebsd/var/run/ld.so.hints
                me@netbsd% ldconfig-freebsd /usr/X11R6/lib /usr/local/lib

          Note that argument directories of ldconfig are mapped to
          /emul/freebsd/XXXX by NetBSD's compat code, and should exist as such
          on your system.  Make sure /emul/freebsd/var/run/ld.so.hints is
          existing when you run FreeBSD's ldconfig, if not, you may lose
          NetBSD's /var/run/ld.so.hints.  FreeBSD ldconfig should be stati-
          cally linked, so it doesn't need any shared libraries by itself.  It
          will create the file /emul/freebsd/var/run/ld.so.hints.  You should
          rerun the FreeBSD version of the ldconfig program each time you add
          a new shared library.

          You should now be set up for FreeBSD binaries which only need a
          shared libc.  You can test this by running the FreeBSD ldd on
          itself.  Suppose that you have it installed as ldd-freebsd, it
          should produce something like:

                me@netbsd% ldd-freebsd `which ldd-freebsd`
                     /usr/local/bin/ldd-freebsd:
                          -lc.2 => /usr/lib/libc.so.2.1 (0x1001a000)

          This being done, you are ready to install new FreeBSD binaries.
          Whenever you install a new FreeBSD program, you should check if it
          needs shared libraries, and if so, whether you have them installed
          in the /emul/freebsd tree.  To do this, you run the FreeBSD version
          ldd on the new program, and watch its output.  ldd (see also the
          manual page for ldd(1)) will print a list of shared libraries that
          the program depends on, in the form -l<majorname> => <fullname>.

          If it prints ``not found'' instead of <fullname> it means that you
          need an extra library.  Which library this is, is shown in <major-
          name>, which will be of the form XXXX.<N> You will need to find a
          libXXXX.so.<N>.<mm> on a FreeBSD ftp site, and install it on your
          system.  The XXXX (name) and <N> (major revision number) should
          match; the minor number(s) <mm> are less important, though it is
          advised to take the most recent version.

     3.   In some cases, FreeBSD binary needs access to certain device file.
          For example, FreeBSD X server software needs FreeBSD /dev/ttyv0 for
          ioctls.  In this case, create a symbolic link from
          /emul/freebsd/dev/ttyv0 to a wscons(4) device file like /dev/ttyE0.
          You will need to have at least options WSDISPLAY_COMPAT_SYSCONS and
          probably also options WSDISPLAY_COMPAT_USL in your kernel (see
          options(4) and wscons(4)).

   Finding the necessary files
     Note: the information below is valid as of the time this document was
     written (June, 1995), but certain details such as names of ftp sites,
     directories and distribution names may have changed by the time you read
     this.

     The FreeBSD distribution is available on a lot of ftp sites.  Sometimes
     the files are unpacked, and you can get the individual files you need,
     but mostly they are stored in distribution sets, usually consisting of
     subdirectories with gzipped tar files in them.  The primary ftp sites for
     the distributions are:
           ftp.freebsd.org:/pub/FreeBSD

     Mirror sites are described on:
           ftp.freebsd.org:/pub/FreeBSD/MIRROR.SITES

     This distribution consists of a number of tar-ed and gzipped files, Nor-
     mally, they're controlled by an install program, but you can retrieve
     files ``by hand'' too.  The way to look something up is to retrieve all
     the files in the distribution, and ``tar ztvf'' through them for the file
     you need.  Here is an example of a list of files that you might need.

           Needed                 Files

           ld.so                  2.0-RELEASE/bindist/bindist.??
           ldconfig               2.0-RELEASE/bindist/bindist.??
           ldd                    2.0-RELEASE/bindist/bindist.??
           libc.so.2              2.0-RELEASE/bindist/bindist.??
           libX11.so.6.0          2.0-RELEASE/XFree86-3.1/XFree86-3.1-bin.tar.gz
           libX11.so.6.0          XFree86-3.1.1/X311bin.tgz
           libXt.so.6.0           2.0-RELEASE/XFree86-3.1/XFree86-3.1-bin.tar.gz
           libXt.so.6.0           XFree86-3.1.1/X311bin.tgz

     The files called ``bindist.??'' are tar-ed, gzipped and split, so you can
     extract contents by ``cat bindist.?? | tar zpxf -''.

     Extract the files from these gzipped tarfiles in your /emul/freebsd
     directory (possibly omitting or afterwards removing files you don't
     need), and you are done.

BUGS
     The information about FreeBSD distributions may become outdated.

NetBSD 5.0_STABLE                June 4, 1995                NetBSD 5.0_STABLE
