| CONFIG(1) | General Commands Manual | CONFIG(1) | 
config —
| config | [ -dMPpSv] [-bbuilddir] [-Dvar=value] [-ssrcdir] [-Uvalue] [config-file] | 
| config | -x[kernel-file] | 
| config | -L[-v]
      [-ssrcdir]
      [config-file] | 
config creates a kernel
  build directory from the machine description file
  config-file, which describes the system to configure.
  Refer to section KERNEL BUILD
  CONFIGURATION for the details of that use of
  config.
In its second synopsis form, config takes
    the binary kernel kernel-file as its single argument
    (aside from the mandatory -x flag), then extracts
    the embedded configuration file (if any) and writes it to standard output.
    If kernel-file is not given, and the system is not
    running NetBSD an error is printed. On systems
    running NetBSD the booted kernel is looked up using
    the sysctl(3) variable
    machdep.booted_kernel and if that is not found,
    _PATH_UNIX (/netbsd) is
    used. Configuration data will be available if the given kernel was compiled
    with either INCLUDE_CONFIG_FILE or
    INCLUDE_JUST_CONFIG options.
In its third synopsis form, config is a
    tool for the kernel developer and generates a “lint”
    configuration file to be used during regression testing. Refer to section
    LINT CONFIGURATION for the
    details of that use of config.
config accepts the following
  parameters:
-b
    builddir-dconfig itself. More -d
      options (currently up to 5) produce more output.-D
    var=valuemakeoptions var=value line to the
      config file.-L-M-P-p-s
    srcdirconfig is used to prepare a kernel build
      directory, but can be relative when it is used in combination with the
      -L flag.-S-U
    varno makeoptions var to the
      config file.-v-xconfig
  program. The traditional way is to run config from the
  conf subdirectory of the machine-specific directory of
  the system source (usually /sys/arch/MACHINE/conf,
  where MACHINE is one of vax,
  hp300, and so forth), and to specify as the
  config-file the name of a machine description file
  located in that directory. config will by default
  create files in the directory ../compile/SYSTEMNAME,
  where SYSTEMNAME is the last path component of
  config-file. config will assume
  that the top-level kernel source directory is located four directories above
  the build directory.
Another way is to create the build directory yourself, place the
    machine description file in the build directory with the name
    CONFIG, and run config from
    within the build directory without specifying a
    config-file. config will then
    by default create files in the current directory. If you run
    config this way, you must specify the location of
    the top-level kernel source directory using the -s
    option or by using the “source”
    directive at the beginning of the machine description file.
Finally, you can specify the build directory for
    config and run it from anywhere. You can specify a
    build directory with the -b option or by using the
    “build” directive at the beginning of
    the machine description file. You must specify the location of the top-level
    kernel source directory if you specify a build directory.
If config-file is a binary kernel,
    config will try to extract the configuration file
    embedded into it, which will be present if that kernel was built either with
    INCLUDE_CONFIG_FILE or
    INCLUDE_JUST_CONFIG options. This work mode requires
    you to manually specify a build directory with the
    -b option, which implies the need to provide a
    source tree too.
If the -p option is supplied,
    .PROF is appended to the default compilation
    directory name, and config acts as if the lines
    “makeoptions PROF="-pg"” and
    “options GPROF” appeared in the
    machine description file. This will build a system that includes profiling
    code; see kgmon(8) and
    gprof(1). The
    -p flag is expected to be used for
    “one-shot” profiles of existing systems; for regular
    profiling, it is probably wiser to create a separate machine description
    file containing the makeoptions line.
The old undocumented -g flag is no longer
    supported. Instead, use “makeoptions
    DEBUG="-g"” and (typically)
    “options KGDB”.
The output of config consists of a number
    of files, principally ioconf.c, a description of I/O
    devices that may be attached to the system; and a
    Makefile, used by
    make(1) in building the
  kernel.
After running config, it is wise to run
    “make depend” in the directory where
    the new makefile was created. config prints a
    reminder of this when it completes.
If config stops due to errors, the
    problems reported should be corrected and config
    should be run again. config attempts to avoid
    changing the compilation directory if there are configuration errors, but
    this code is not well-tested, and some problems (such as running out of disk
    space) are unrecoverable.
When used with the -L flag,
    config takes the regular configuration file
    config-file and prints on the standard output a
    configuration file that includes config-file, selects
    all options and file-systems the user can possibly select, and defines an
    instance of every possible attachment as described by the kernel option
    definition files used by config-file.
The resulting configuration file is meant as a way to select all possible features in order to test that each of them compiles. It is not meant to result in a kernel binary that can run on any hardware.
Unlike the first synopsis form, the provided srcdir is relative to the current working directory. In the first synopsis form, it is relative to the build directory.
config command appeared in
  4.1BSD. It was completely revised in
  4.4BSD. The -x option appeared
  in NetBSD 2.0. The -L option
  appeared in NetBSD 5.0.
| September 1, 2015 | NetBSD 10.0 |