bsd/man/man9/intro.9

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