INTRO(9)               FreeBSD Kernel Developer's Manual              INTRO(9)

NAME
     intro - introduction to system kernel interfaces

DESCRIPTION
     This section contains information about the interfaces and subroutines in
     the kernel.

PROTOTYPES ANSI-C AND ALL THAT
     Yes please.

     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
     shutting 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.

NAMING THINGS
     Some general rules exist:

     1.   If a function is meant as a debugging aid in DDB, it should be
          enclosed in

                #ifdef DDB

                #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
     opposite.

     There are several reasons for this policy, the main one is that the
     kernel is one monolithic name-space, and pollution is not a good idea
     here either.

     For device drivers and other modules that do not add new internal
     interfaces 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.

SEE ALSO
     style(9)

HISTORY
     The intro section manual page appeared in FreeBSD 2.2.

FreeBSD 13.1-RELEASE-p6        December 13, 1995       FreeBSD 13.1-RELEASE-p6