NAME    [Toc]    [Back]

     linux -- Linux ABI support

SYNOPSIS    [Toc]    [Back]

     To link Linux ABI support into the kernel:
     options COMPAT_LINUX

     To load the Linux ABI support kernel module:
	   kldload linux

DESCRIPTION    [Toc]    [Back]

     The linux module provides limited Linux ABI (application binary interface)
 compatibility for userland applications.  The module provides the
     following significant facilities:

     +o	 An image activator for correctly branded elf(5) executable images

     +o	 Special signal handling for activated images

     +o	 Linux to native system call translation

     It is important to note that the Linux ABI support it not provided
     through an emulator.  Rather, a true (albeit limited) ABI implementation
     is provided.

     The following sysctl(8) tunable variables are available:

     compat.linux.osname       Linux kernel operating system name.

     compat.linux.osrelease    Linux kernel operating system release.

     compat.linux.oss_version  Linux Open Sound System version.

     The linux module can be linked into the kernel statically with the
     COMPAT_LINUX kernel configuration option or loaded as required.  The following
 command will load the module if it is neither linked into the kernel
 nor already loaded as a module:

	   if ! kldstat -v | grep -E 'linux(aout|elf)' > /dev/null; then
		   kldload linux > /dev/null 2>&1
	   fi

     Note that dynamically linked Linux executables will require a suitable
     environment in /compat/linux.  Specifically, the Linux run-time linker's
     hints files should be correctly initialized.  For this reason, it is common
 to execute the following commands to prepare the system to correctly
     run Linux executables:

	   if [ -x /compat/linux/sbin/ldconfig ]; then
		   /compat/linux/sbin/ldconfig
	   fi

     For information on loading the linux kernel loadable module automatically
     on system startup, see rc.conf(5).  This information applies regardless
     of whether the linux module is statically linked into the kernel or
     loaded as a module.

FILES    [Toc]    [Back]

     /compat/linux	 minimal Linux run-time environment
     /compat/linux/proc  limited Linux process file system

SEE ALSO    [Toc]    [Back]

     brandelf(1), elf(5), linprocfs(5)

HISTORY    [Toc]    [Back]

     Linux ABI support first appeared in FreeBSD 2.1.


FreeBSD 5.2.1			August 17, 2000 		 FreeBSD 5.2.1