utility builds a set of system configuration files from the file
the system to configure.
A second file
what files are needed to generate a system and
can be augmented by configuration specific set of files
that give alternate files for a specific machine
Available options and operands:
If the INCLUDE_CONFIG_FILE is present in a configuration file,
kernel image will contain full configuration files included
literally (preserving comments).
This flag is kept for backward compatibility.
as the output directory, instead of the default one.
does not append
to the directory given.
Configure a system for debugging.
Print kernel configuration file embedded into a kernel
This option makes sense only if
entry was present in your configuration file.
Configure a system for profiling; for example,
If two or more
options are supplied,
configures a system for high resolution profiling.
Specify the name of the system configuration file
containing device specifications, configuration options
and other system parameters for one system configuration.
utility should be run from the
subdirectory of the system source (usually
/sys/ ARCH /conf
represents one of the architectures supported by
utility creates the directory
or the one given with the
as necessary and places all output files there.
The output of
consists of a number of files; for the
in building the system;
the number of various devices that will be compiled into the system.
it is necessary to run
in the directory where the new makefile
utility prints a reminder of this when it completes.
If any other error messages are produced by
the problems in the configuration file should be corrected and
should be run again.
Attempts to compile a system that had configuration errors
are likely to fail.
BSD kernels are compiled without symbols due to the heavy load on the
system when compiling a
A debug kernel contains complete symbols for all the source files, and
enables an experienced kernel programmer to analyse the cause of a problem.
debuggers available prior to
BSD 4.4 Lite
were able to find some information
from a normal kernel;
provides very little support for normal kernels, and a debug kernel is needed
for any meaningful analysis.
For reasons of history, time and space, building a debug kernel is not the
a debug kernel takes up to 30% longer to build and
requires about 30 MB of disk storage in the build directory, compared to about 6
MB for a non-debug kernel.
A debug kernel is about 11 MB in size, compared to
about 2 MB for a non-debug kernel.
This space is used both in the root file
system and at run time in memory.
option to build a debug kernel.
With this option,
causes two kernel files to be built in the kernel build directory:
is the complete debug kernel.
is a copy of the kernel with the debug symbols stripped off.
This is equivalent
to the normal non-debug kernel.
There is currently little sense in installing and booting from a debug kernel,
since the only tools available which use the symbols do not run on-line.
are therefore two options for installing a debug kernel:
in the root file system.
in the root file system.
list of common files system is built from
generic makefile for the
/sys/ ARCH /compile/ SYSTEM_NAME
default kernel build directory for system
portion of each device in section 4.
"Building 4.3 BSD UNIX System with Config"
utility appeared in
Before support for
included entire configuration file that used to be embedded in
the new kernel.
This meant that
could be used to extract it from a kernel:
to extract the configuration information, you had to use
"strings -n 3 kernel | sed -n 's/^___//p'"
The line numbers reported in error messages are usually off by one.