1 .\" Copyright (c) 2000 Sheldon Hearn
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34 To compile support for this ABI into the kernel,
35 place the following line in your
36 kernel configuration file:
37 .Bd -ragged -offset indent
38 .Cd "options COMPAT_LINUX"
41 Alternatively, to load the ABI as a
42 module at boot time, place the following line in
44 .Bd -literal -offset indent
50 module provides limited
51 Linux ABI (application binary interface) compatibility
52 for userland applications.
53 The module provides the following significant facilities:
61 Special signal handling for activated images
63 Linux to native system call translation
66 It is important to note that the Linux ABI support
67 it not provided through an emulator.
68 Rather, a true (albeit limited) ABI implementation is provided.
72 tunable variables are available:
73 .Bl -tag -width compat.linux.oss_version
74 .It compat.linux.osname
75 Linux kernel operating system name.
76 .It compat.linux.osrelease
77 Linux kernel operating system release.
78 Changing this to something else is discouraged on non-development systems,
79 because it may change the way Linux programs work.
80 Recent versions of GNU libc are known to use different syscalls depending
81 on the value of this sysctl.
82 .It compat.linux.oss_version
83 Linux Open Sound System version.
88 module can be linked into the kernel statically with the
90 kernel configuration option
91 or loaded as required.
92 The following command will load the module
93 if it is neither linked into the kernel
94 nor already loaded as a module:
95 .Bd -literal -offset indent
96 if ! kldstat -v | grep -E 'linux(aout|elf)' > /dev/null; then
97 kldload linux > /dev/null 2>&1
101 Note that dynamically linked Linux executables
102 will require a suitable environment in
104 Specifically, the Linux run-time linker's hints files
105 should be correctly initialized.
106 For this reason, it is common to execute the following commands
107 to prepare the system to correctly run Linux executables:
108 .Bd -literal -offset indent
109 if [ -x /compat/linux/sbin/ldconfig ]; then
110 /compat/linux/sbin/ldconfig -r /compat/linux
114 For information on loading the
116 kernel loadable module automatically on system startup,
119 This information applies
120 regardless of whether the
122 module is statically linked into the kernel
123 or loaded as a module.
125 .Bl -tag -width /compat/linux/proc -compact
127 minimal Linux run-time environment
128 .It Pa /compat/linux/proc
129 limited Linux process file system
130 .It Pa /compat/linux/sys
131 limited Linux system file system
139 Linux ABI support first appeared in