[PATCH 07/10] docs: kernel-doc.rst: add documentation about man pages

[Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>]

kernel-doc-nano-HOWTO.txt has a chapter about man pages
production. While we don't have a working  "make manpages"
target, add it.

Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
---
 Documentation/doc-guide/kernel-doc.rst | 61 ++++++++++++++++++++++++++--------
 1 file changed, 47 insertions(+), 14 deletions(-)

diff --git a/Documentation/doc-guide/kernel-doc.rst b/Documentation/doc-guide/kernel-doc.rst
index 9777aa53e3dd..50473f0db345 100644
--- a/Documentation/doc-guide/kernel-doc.rst
+++ b/Documentation/doc-guide/kernel-doc.rst
@@ -377,7 +377,6 @@ cross-references.
 For further details, please refer to the `Sphinx C Domain`_ documentation.
 
 
-
 In-line member documentation comments
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
@@ -391,19 +390,19 @@ on a line of their own, like all other kernel-doc comments::
    * @foo: The Foo member.
    */
   struct foo {
-        int foo;
-        /**
-         * @bar: The Bar member.
-         */
-        int bar;
-        /**
-         * @baz: The Baz member.
-         *
-         * Here, the member description may contain several paragraphs.
-         */
-        int baz;
-        /** @foobar: Single line description. */
-        int foobar;
+	int foo;
+	/**
+	 * @bar: The Bar member.
+	 */
+	int bar;
+	/**
+	 * @baz: The Baz member.
+	 *
+	 * Here, the member description may contain several paragraphs.
+	 */
+	int baz;
+	/** @foobar: Single line description. */
+	int foobar;
   }
 
 
@@ -452,3 +451,37 @@ file.
 
 Data structures visible in kernel include files should also be documented using
 kernel-doc formatted comments.
+
+How to use kernel-doc to generate man pages
+-------------------------------------------
+
+If you just want to use kernel-doc to generate man pages you can do this
+from the Kernel git tree::
+
+  $ scripts/kernel-doc -man $(git grep -l '/\*\*' |grep -v Documentation/) | ./split-man.pl /tmp/man
+
+Using the small ``split-man.pl`` script below::
+
+
+  #!/usr/bin/perl
+
+  if ($#ARGV < 0) {
+     die "where do I put the results?\n";
+  }
+
+  mkdir $ARGV[0],0777;
+  $state = 0;
+  while (<STDIN>) {
+      if (/^\.TH \"[^\"]*\" 9 \"([^\"]*)\"/) {
+	if ($state == 1) { close OUT }
+	$state = 1;
+	$fn = "$ARGV[0]/$1.9";
+	print STDERR "Creating $fn\n";
+	open OUT, ">$fn" or die "can't open $fn: $!\n";
+	print OUT $_;
+      } elsif ($state != 0) {
+	print OUT $_;
+      }
+  }
+
+  close OUT;
-- 
2.13.5