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@@ -1,6 +1,105 @@
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kernel-doc nano-HOWTO
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=====================
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+How to format kernel-doc comments
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+---------------------------------
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+
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+In order to provide embedded, 'C' friendly, easy to maintain,
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+but consistent and extractable documentation of the functions and
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+data structures in the Linux kernel, the Linux kernel has adopted
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+a consistent style for documenting functions and their parameters,
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+and structures and their members.
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+
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+The format for this documentation is called the kernel-doc format.
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+It is documented in this Documentation/kernel-doc-nano-HOWTO.txt file.
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+
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+This style embeds the documentation within the source files, using
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+a few simple conventions. The scripts/kernel-doc perl script, some
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+SGML templates in Documentation/DocBook, and other tools understand
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+these conventions, and are used to extract this embedded documentation
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+into various documents.
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+
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+In order to provide good documentation of kernel functions and data
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+structures, please use the following conventions to format your
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+kernel-doc comments in Linux kernel source.
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+
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+We definitely need kernel-doc formatted documentation for functions
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+that are exported to loadable modules using EXPORT_SYMBOL.
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+
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+We also look to provide kernel-doc formatted documentation for
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+functions externally visible to other kernel files (not marked
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+"static").
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+
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+We also recommend providing kernel-doc formatted documentation
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+for private (file "static") routines, for consistency of kernel
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+source code layout. But this is lower priority and at the
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+discretion of the MAINTAINER of that kernel source file.
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+
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+Data structures visible in kernel include files should also be
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+documented using kernel-doc formatted comments.
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+
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+The opening comment mark "/**" is reserved for kernel-doc comments.
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+Only comments so marked will be considered by the kernel-doc scripts,
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+and any comment so marked must be in kernel-doc format. Do not use
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+"/**" to be begin a comment block unless the comment block contains
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+kernel-doc formatted comments. The closing comment marker for
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+kernel-doc comments can be either "*/" or "**/".
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+
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+Kernel-doc comments should be placed just before the function
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+or data structure being described.
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+
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+Example kernel-doc function comment:
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+
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+/**
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+ * foobar() - short function description of foobar
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+ * @arg1: Describe the first argument to foobar.
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+ * @arg2: Describe the second argument to foobar.
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+ * One can provide multiple line descriptions
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+ * for arguments.
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+ *
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+ * A longer description, with more discussion of the function foobar()
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+ * that might be useful to those using or modifying it. Begins with
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+ * empty comment line, and may include additional embedded empty
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+ * comment lines.
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+ *
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+ * The longer description can have multiple paragraphs.
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+ **/
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+
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+The first line, with the short description, must be on a single line.
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+
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+The @argument descriptions must begin on the very next line following
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+this opening short function description line, with no intervening
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+empty comment lines.
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+
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+Example kernel-doc data structure comment.
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+
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+/**
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+ * struct blah - the basic blah structure
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+ * @mem1: describe the first member of struct blah
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+ * @mem2: describe the second member of struct blah,
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+ * perhaps with more lines and words.
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+ *
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+ * Longer description of this structure.
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+ **/
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+
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+The kernel-doc function comments describe each parameter to the
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+function, in order, with the @name lines.
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+
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+The kernel-doc data structure comments describe each structure member
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+in the data structure, with the @name lines.
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+
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+The longer description formatting is "reflowed", losing your line
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+breaks. So presenting carefully formatted lists within these
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+descriptions won't work so well; derived documentation will lose
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+the formatting.
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+
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+See the section below "How to add extractable documentation to your
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+source files" for more details and notes on how to format kernel-doc
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+comments.
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+
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+Components of the kernel-doc system
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+-----------------------------------
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+
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Many places in the source tree have extractable documentation in the
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form of block comments above functions. The components of this system
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are:
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