4 Many places in the source tree have extractable documentation in the
5 form of block comments above functions. The components of this system
10 This is a perl script that hunts for the block comments and can mark
11 them up directly into DocBook, man, text, and HTML. (No, not
14 - Documentation/DocBook/*.tmpl
16 These are SGML template files, which are normal SGML files with
17 special place-holders for where the extracted documentation should
22 This is a program for converting SGML template files into SGML
23 files. It invokes kernel-doc, giving it the list of functions that
26 - scripts/gen-all-syms
28 This is a script that lists the EXPORT_SYMBOL symbols in a list of C
33 This script invokes docproc, telling it which functions are to be
34 documented (this list comes from gen-all-syms).
38 The targets 'sgmldocs', 'psdocs', and 'pdfdocs' are used to build
39 DocBook files, PostScript files, and PDF files in
40 Documentation/DocBook.
42 - Documentation/DocBook/Makefile
44 This is where C files are associated with SGML templates.
47 How to extract the documentation
48 --------------------------------
50 If you just want to read the ready-made books on the various
51 subsystems (see Documentation/DocBook/*.tmpl), just type 'make
52 psdocs', or 'make pdfdocs', depending on your preference. If you
53 would rather read a different format, you can type 'make sgmldocs' and
54 then use DocBook tools to convert Documentation/DocBook/*.sgml to a
55 format of your choice (for example, 'db2html ...').
57 If you want to see man pages instead, you can do this:
60 $ scripts/kernel-doc -man $(find -name '*.c' '*.h') | split-man.pl /tmp/man
68 die "where do I put the results?\n";
71 mkdir $ARGV[0],0777 or die "Can't create $ARGV[0]: $!\n";
74 if (/^\.TH \"[^\"]*\" 4 \"([^\"]*)\"/) {
75 if ($state == 1) { close OUT }
77 $fn = "$ARGV[0]/$1.4";
78 print STDERR "Creating $fn\n";
79 open OUT, ">$fn" or die "can't open $fn: $!\n";
81 } elsif ($state != 0) {
89 If you just want to view the documentation for one function in one
90 file, you can do this:
92 $ scripts/kernel-doc -man -function fn file | nroff -man | less
96 $ scripts/kernel-doc -text -function fn file
99 How to add extractable documentation to your source files
100 ---------------------------------------------------------
102 The format of the block comment is like this:
105 * function_name(:)? (- short description)?
106 (* @parameterx: (description of parameter x)?)*
108 * (Description:)? (Description of function)?
109 * (section header: (section description)? )*
112 The short function description cannot be multiline, but the other
115 All descriptive text is further processed, scanning for the following special
116 patterns, which are highlighted appropriately.
118 'funcname()' - function
119 '$ENVVAR' - environment variable
120 '&struct_name' - name of a structure (up to two words including 'struct')
121 '@parameter' - name of a parameter
122 '%CONST' - name of a constant.
124 Take a look around the source tree for examples.
127 How to make new SGML template files
128 -----------------------------------
130 SGML template files (*.tmpl) are like normal SGML files, except that
131 they can contain escape sequences where extracted documentation should
134 !E<filename> is replaced by the documentation, in <filename>, for
135 functions that are exported using EXPORT_SYMBOL: the function list is
136 collected from files listed in Documentation/DocBook/Makefile.
138 !I<filename> is replaced by the documentation for functions that are
139 _not_ exported using EXPORT_SYMBOL.
141 !F<filename> <function [functions...]> is replaced by the
142 documentation, in <filename>, for the functions listed.
146 */ <twaugh@redhat.com>