xref: /dragonfly/share/man/man9/intro.9 (revision dc71b7ab)
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31.Dd December 13, 1995
32.Dt INTRO 9
33.Os
34.Sh NAME
35.Nm intro
36.Nd "introduction to system kernel interfaces"
37.Sh DESCRIPTION
38This section contains information about the interfaces and
39subroutines in the kernel.
40.Sh PROTOTYPES ANSI-C AND ALL THAT
41Yes please.
42.Pp
43We would like all code to be fully prototyped.
44.Pp
45If your code compiles cleanly with
46.Nm cc
47.Ar -Wall
48we would feel happy about it.
49It is important to understand that this isn't a question of just shutting up
50.Nm cc ,
51it is a question about avoiding the things it complains about.
52To put it bluntly, don't hide the problem by casting and other
53obfuscating practices, solve the problem.
54.Sh INDENTATION AND STYLE
55Believe it or not, there actually exists a guide for indentation and style.
56It isn't generally applied though.
57.Pp
58We would appreciate if people would pay attention to it, and at least not
59violate it blatantly.
60.Pp
61We don't mind it too badly if you have your own style, but please make
62sure we can read it too.
63.Pp
64Please take time to read
65.Xr style 9
66for more information.
67.Sh NAMING THINGS
68Some general rules exist:
69.Bl -enum
70.It
71If a function is meant as a debugging aid in DDB, it should be enclosed
72in
73.Bd -literal -offset indent
74#ifdef DDB
75
76#endif /* DDB */
77.Ed
78.Pp
79And the name of the procedure should start with the prefix
80.Li DDB_
81to clearly identify the procedure as a debugger routine.
82.El
83.Sh SCOPE OF SYMBOLS
84It is important to carefully consider the scope of symbols in the kernel.
85The default is to make everything static, unless some reason requires
86the opposite.
87.Pp
88There are several reasons for this policy,
89the main one is that the kernel is one monolithic name-space,
90and pollution is not a good idea here either.
91.Pp
92For device drivers and other modules that don't add new internal interfaces
93to the kernel, the entire source should be in one file if possible.
94That way all symbols can be made static.
95.Pp
96If for some reason a module is split over multiple source files, then try
97to split the module along some major fault-line and consider using the
98number of global symbols as your guide.
99The fewer the better.
100.Sh SEE ALSO
101.Xr style 9
102.Sh HISTORY
103The
104.Nm
105section manual page appeared in
106.Fx 2.2 .
107