INTRO(9) BSD Kernel Developer's Manual INTRO(9)NAMEintro — introduction to system kernel interfaces
This section contains information about the interfaces and subroutines in
PROTOTYPES ANSI-C AND ALL THAT
We would like all code to be fully prototyped.
If your code compiles cleanly with cc -Wall we would feel happy about it.
It is important to understand that this is not a question of just shut‐
ting up cc, it is a question about avoiding the things it complains
about. To put it bluntly, do not hide the problem by casting and other
obfuscating practices, solve the problem.
INDENTATION AND STYLE
Believe it or not, there actually exists a guide for indentation and
style. It is not generally applied though.
We would appreciate if people would pay attention to it, and at least not
violate it blatantly.
We do not mind it too badly if you have your own style, but please make
sure we can read it too.
Please take time to read style(9) for more information.
Some general rules exist:
1. If a function is meant as a debugging aid in DDB, it should be
#endif /* DDB */
And the name of the procedure should start with the prefix DDB_ to
clearly identify the procedure as a debugger routine.
SCOPE OF SYMBOLS
It is important to carefully consider the scope of symbols in the kernel.
The default is to make everything static, unless some reason requires the
There are several reasons for this policy, the main one is that the ker‐
nel is one monolithic name-space, and pollution is not a good idea here
For device drivers and other modules that do not add new internal inter‐
faces to the kernel, the entire source should be in one file if possible.
That way all symbols can be made static.
If for some reason a module is split over multiple source files, then try
to split the module along some major fault-line and consider using the
number of global symbols as your guide. The fewer the better.
The intro section manual page appeared in FreeBSD 2.2.
BSD December 13, 1995 BSD