Annotation of /alx-src/trunk/kernel26-alx/linux/Documentation/SubmittingPatches


	How to Get Your Change Into the Linux Kernel
		or
	Care And Operation Of Your Linus Torvalds


For a person or company who wishes to submit a change to the Linux
kernel, the process can sometimes be daunting if you're not familiar
with "the system."  This text is a collection of suggestions which
can greatly increase the chances of your change being accepted.

If you are submitting a driver, also read Documentation/SubmittingDrivers.


--------------------------------------------
SECTION 1 - CREATING AND SENDING YOUR CHANGE
--------------------------------------------


1) "diff -up"
------------

Use "diff -up" or "diff -uprN" to create patches.

All changes to the Linux kernel occur in the form of patches, as
generated by diff(1).  When creating your patch, make sure to create it
in "unified diff" format, as supplied by the '-u' argument to diff(1).
Also, please use the '-p' argument which shows which C function each
change is in - that makes the resultant diff a lot easier to read.
Patches should be based in the root kernel source directory,
not in any lower subdirectory.

To create a patch for a single file, it is often sufficient to do:

	SRCTREE= linux-2.4
	MYFILE=  drivers/net/mydriver.c

	cd $SRCTREE
	cp $MYFILE $MYFILE.orig
	vi $MYFILE	# make your change
	cd ..
	diff -up $SRCTREE/$MYFILE{.orig,} > /tmp/patch

To create a patch for multiple files, you should unpack a "vanilla",
or unmodified kernel source tree, and generate a diff against your
own source tree.  For example:

	MYSRC= /devel/linux-2.4

	tar xvfz linux-2.4.0-test11.tar.gz
	mv linux linux-vanilla
	wget http://www.moses.uklinux.net/patches/dontdiff
	diff -uprN -X dontdiff linux-vanilla $MYSRC > /tmp/patch
	rm -f dontdiff

"dontdiff" is a list of files which are generated by the kernel during
the build process, and should be ignored in any diff(1)-generated
patch.  dontdiff is maintained by Tigran Aivazian <tigran@veritas.com>

Make sure your patch does not include any extra files which do not
belong in a patch submission.  Make sure to review your patch -after-
generated it with diff(1), to ensure accuracy.

If your changes produce a lot of deltas, you may want to look into
splitting them into individual patches which modify things in
logical stages, this will facilitate easier reviewing by other
kernel developers, very important if you want your patch accepted.
There are a number of scripts which can aid in this;

Quilt:
http://savannah.nongnu.org/projects/quilt

Randy Dunlap's patch scripts:
http://developer.osdl.org/rddunlap/scripts/patching-scripts.tgz

Andrew Morton's patch scripts:
http://www.zip.com.au/~akpm/linux/patches/patch-scripts-0.16

2) Describe your changes.

Describe the technical detail of the change(s) your patch includes.

Be as specific as possible.  The WORST descriptions possible include
things like "update driver X", "bug fix for driver X", or "this patch
includes updates for subsystem X.  Please apply."

If your description starts to get long, that's a sign that you probably
need to split up your patch.  See #3, next.


3) Separate your changes.

Separate each logical change into its own patch.

For example, if your changes include both bug fixes and performance
enhancements for a single driver, separate those changes into two
or more patches.  If your changes include an API update, and a new
driver which uses that new API, separate those into two patches.

On the other hand, if you make a single change to numerous files,
group those changes into a single patch.  Thus a single logical change
is contained within a single patch.

If one patch depends on another patch in order for a change to be
complete, that is OK.  Simply note "this patch depends on patch X"
in your patch description.


4) Select e-mail destination.

Look through the MAINTAINERS file and the source code, and determine
if your change applies to a specific subsystem of the kernel, with
an assigned maintainer.  If so, e-mail that person.

If no maintainer is listed, or the maintainer does not respond, send
your patch to the primary Linux kernel developer's mailing list,
linux-kernel@vger.kernel.org.  Most kernel developers monitor this
e-mail list, and can comment on your changes.

Linus Torvalds is the final arbiter of all changes accepted into the
Linux kernel.  His e-mail address is <torvalds@osdl.org>.  He gets
a lot of e-mail, so typically you should do your best to -avoid- sending
him e-mail.

Patches which are bug fixes, are "obvious" changes, or similarly
require little discussion should be sent or CC'd to Linus.  Patches
which require discussion or do not have a clear advantage should
usually be sent first to linux-kernel.  Only after the patch is
discussed should the patch then be submitted to Linus.

For small patches you may want to CC the Trivial Patch Monkey
trivial@rustcorp.com.au set up by Rusty Russell; which collects "trivial"
patches. Trivial patches must qualify for one of the following rules:
 Spelling fixes in documentation
 Spelling fixes which could break grep(1).
 Warning fixes (cluttering with useless warnings is bad)
 Compilation fixes (only if they are actually correct)
 Runtime fixes (only if they actually fix things)
 Removing use of deprecated functions/macros (eg. check_region).
 Contact detail and documentation fixes
 Non-portable code replaced by portable code (even in arch-specific,
 since people copy, as long as it's trivial)
 Any fix by the author/maintainer of the file. (ie. patch monkey
 in re-transmission mode)


5) Select your CC (e-mail carbon copy) list.

Unless you have a reason NOT to do so, CC linux-kernel@vger.kernel.org.

Other kernel developers besides Linus need to be aware of your change,
so that they may comment on it and offer code review and suggestions.
linux-kernel is the primary Linux kernel developer mailing list.
Other mailing lists are available for specific subsystems, such as
USB, framebuffer devices, the VFS, the SCSI subsystem, etc.  See the
MAINTAINERS file for a mailing list that relates specifically to
your change.

Even if the maintainer did not respond in step #4, make sure to ALWAYS
copy the maintainer when you change their code.

For small patches you may want to CC the Trivial Patch Monkey
trivial@rustcorp.com.au set up by Rusty Russell; which collects "trivial"
patches. Trivial patches must qualify for one of the following rules:
 Spelling fixes in documentation
 Spelling fixes which could break grep(1).
 Warning fixes (cluttering with useless warnings is bad)
 Compilation fixes (only if they are actually correct)
 Runtime fixes (only if they actually fix things)
 Removing use of deprecated functions/macros (eg. check_region).
 Contact detail and documentation fixes
 Non-portable code replaced by portable code (even in arch-specific,
 since people copy, as long as it's trivial)
 Any fix by the author/maintainer of the file. (ie. patch monkey
 in re-transmission mode)


6) No MIME, no links, no compression, no attachments.  Just plain text.

Linus and other kernel developers need to be able to read and comment
on the changes you are submitting.  It is important for a kernel
developer to be able to "quote" your changes, using standard e-mail
tools, so that they may comment on specific portions of your code.

For this reason, all patches should be submitting e-mail "inline".
WARNING:  Be wary of your editor's word-wrap corrupting your patch,
if you choose to cut-n-paste your patch.

Do not attach the patch as a MIME attachment, compressed or not.
Many popular e-mail applications will not always transmit a MIME
attachment as plain text, making it impossible to comment on your
code.  A MIME attachment also takes Linus a bit more time to process,
decreasing the likelihood of your MIME-attached change being accepted.

Exception:  If your mailer is mangling patches then someone may ask
you to re-send them using MIME.


7) E-mail size.

When sending patches to Linus, always follow step #6.

Large changes are not appropriate for mailing lists, and some
maintainers.  If your patch, uncompressed, exceeds 40 kB in size,
it is preferred that you store your patch on an Internet-accessible
server, and provide instead a URL (link) pointing to your patch.


8) Name your kernel version.

It is important to note, either in the subject line or in the patch
description, the kernel version to which this patch applies.

If the patch does not apply cleanly to the latest kernel version,
Linus will not apply it.


9) Don't get discouraged.  Re-submit.

After you have submitted your change, be patient and wait.  If Linus
likes your change and applies it, it will appear in the next version
of the kernel that he releases.

However, if your change doesn't appear in the next version of the
kernel, there could be any number of reasons.  It's YOUR job to
narrow down those reasons, correct what was wrong, and submit your
updated change.

It is quite common for Linus to "drop" your patch without comment.
That's the nature of the system.  If he drops your patch, it could be
due to
* Your patch did not apply cleanly to the latest kernel version
* Your patch was not sufficiently discussed on linux-kernel.
* A style issue (see section 2),
* An e-mail formatting issue (re-read this section)
* A technical problem with your change
* He gets tons of e-mail, and yours got lost in the shuffle
* You are being annoying (See Figure 1)

When in doubt, solicit comments on linux-kernel mailing list.


10) Include PATCH in the subject

Due to high e-mail traffic to Linus, and to linux-kernel, it is common
convention to prefix your subject line with [PATCH].  This lets Linus
and other kernel developers more easily distinguish patches from other
e-mail discussions.


11) Sign your work

To improve tracking of who did what, especially with patches that can
percolate to their final resting place in the kernel through several
layers of maintainers, we've introduced a "sign-off" procedure on
patches that are being emailed around.

The sign-off is a simple line at the end of the explanation for the
patch, which certifies that you wrote it or otherwise have the right to
pass it on as a open-source patch.  The rules are pretty simple: if you
can certify the below:

        Developer's Certificate of Origin 1.1

        By making a contribution to this project, I certify that:

        (a) The contribution was created in whole or in part by me and I
            have the right to submit it under the open source license
            indicated in the file; or

        (b) The contribution is based upon previous work that, to the best
            of my knowledge, is covered under an appropriate open source
            license and I have the right under that license to submit that
            work with modifications, whether created in whole or in part
            by me, under the same open source license (unless I am
            permitted to submit under a different license), as indicated
            in the file; or

        (c) The contribution was provided directly to me by some other
            person who certified (a), (b) or (c) and I have not modified
            it.

	(d) I understand and agree that this project and the contribution
	    are public and that a record of the contribution (including all
	    personal information I submit with it, including my sign-off) is
	    maintained indefinitely and may be redistributed consistent with
	    this project or the open source license(s) involved.

then you just add a line saying

	Signed-off-by: Random J Developer <random@developer.org>

Some people also put extra tags at the end.  They'll just be ignored for
now, but you can do this to mark internal company procedures or just
point out some special detail about the sign-off. 


-----------------------------------
SECTION 2 - HINTS, TIPS, AND TRICKS
-----------------------------------

This section lists many of the common "rules" associated with code
submitted to the kernel.  There are always exceptions... but you must
have a really good reason for doing so.  You could probably call this
section Linus Computer Science 101.


1) Read Documentation/CodingStyle

Nuff said.  If your code deviates too much from this, it is likely
to be rejected without further review, and without comment.


2) #ifdefs are ugly

Code cluttered with ifdefs is difficult to read and maintain.  Don't do
it.  Instead, put your ifdefs in a header, and conditionally define
'static inline' functions, or macros, which are used in the code.
Let the compiler optimize away the "no-op" case.

Simple example, of poor code:

	dev = alloc_etherdev (sizeof(struct funky_private));
	if (!dev)
		return -ENODEV;
	#ifdef CONFIG_NET_FUNKINESS
	init_funky_net(dev);
	#endif

Cleaned-up example:

(in header)
	#ifndef CONFIG_NET_FUNKINESS
	static inline void init_funky_net (struct net_device *d) {}
	#endif

(in the code itself)
	dev = alloc_etherdev (sizeof(struct funky_private));
	if (!dev)
		return -ENODEV;
	init_funky_net(dev);


3) 'static inline' is better than a macro

Static inline functions are greatly preferred over macros.
They provide type safety, have no length limitations, no formatting
limitations, and under gcc they are as cheap as macros.

Macros should only be used for cases where a static inline is clearly
suboptimal [there a few, isolated cases of this in fast paths],
or where it is impossible to use a static inline function [such as
string-izing].

'static inline' is preferred over 'static __inline__', 'extern inline',
and 'extern __inline__'.


4) Don't over-design.

Don't try to anticipate nebulous future cases which may or may not
be useful:  "Make it as simple as you can, and no simpler"


1	niro	628
2			How to Get Your Change Into the Linux Kernel
3			or
4			Care And Operation Of Your Linus Torvalds
5
6
7
8			For a person or company who wishes to submit a change to the Linux
9			kernel, the process can sometimes be daunting if you're not familiar
10			with "the system." This text is a collection of suggestions which
11			can greatly increase the chances of your change being accepted.
12
13			If you are submitting a driver, also read Documentation/SubmittingDrivers.
14
15
16
17			--------------------------------------------
18			SECTION 1 - CREATING AND SENDING YOUR CHANGE
19			--------------------------------------------
20
21
22
23			1) "diff -up"
24			------------
25
26			Use "diff -up" or "diff -uprN" to create patches.
27
28			All changes to the Linux kernel occur in the form of patches, as
29			generated by diff(1). When creating your patch, make sure to create it
30			in "unified diff" format, as supplied by the '-u' argument to diff(1).
31			Also, please use the '-p' argument which shows which C function each
32			change is in - that makes the resultant diff a lot easier to read.
33			Patches should be based in the root kernel source directory,
34			not in any lower subdirectory.
35
36			To create a patch for a single file, it is often sufficient to do:
37
38			SRCTREE= linux-2.4
39			MYFILE= drivers/net/mydriver.c
40
41			cd $SRCTREE
42			cp $MYFILE $MYFILE.orig
43			vi $MYFILE # make your change
44			cd ..
45			diff -up $SRCTREE/$MYFILE{.orig,} > /tmp/patch
46
47			To create a patch for multiple files, you should unpack a "vanilla",
48			or unmodified kernel source tree, and generate a diff against your
49			own source tree. For example:
50
51			MYSRC= /devel/linux-2.4
52
53			tar xvfz linux-2.4.0-test11.tar.gz
54			mv linux linux-vanilla
55			wget http://www.moses.uklinux.net/patches/dontdiff
56			diff -uprN -X dontdiff linux-vanilla $MYSRC > /tmp/patch
57			rm -f dontdiff
58
59			"dontdiff" is a list of files which are generated by the kernel during
60			the build process, and should be ignored in any diff(1)-generated
61			patch. dontdiff is maintained by Tigran Aivazian <tigran@veritas.com>
62
63			Make sure your patch does not include any extra files which do not
64			belong in a patch submission. Make sure to review your patch -after-
65			generated it with diff(1), to ensure accuracy.
66
67			If your changes produce a lot of deltas, you may want to look into
68			splitting them into individual patches which modify things in
69			logical stages, this will facilitate easier reviewing by other
70			kernel developers, very important if you want your patch accepted.
71			There are a number of scripts which can aid in this;
72
73			Quilt:
74			http://savannah.nongnu.org/projects/quilt
75
76			Randy Dunlap's patch scripts:
77			http://developer.osdl.org/rddunlap/scripts/patching-scripts.tgz
78
79			Andrew Morton's patch scripts:
80			http://www.zip.com.au/~akpm/linux/patches/patch-scripts-0.16
81
82			2) Describe your changes.
83
84			Describe the technical detail of the change(s) your patch includes.
85
86			Be as specific as possible. The WORST descriptions possible include
87			things like "update driver X", "bug fix for driver X", or "this patch
88			includes updates for subsystem X. Please apply."
89
90			If your description starts to get long, that's a sign that you probably
91			need to split up your patch. See #3, next.
92
93
94
95			3) Separate your changes.
96
97			Separate each logical change into its own patch.
98
99			For example, if your changes include both bug fixes and performance
100			enhancements for a single driver, separate those changes into two
101			or more patches. If your changes include an API update, and a new
102			driver which uses that new API, separate those into two patches.
103
104			On the other hand, if you make a single change to numerous files,
105			group those changes into a single patch. Thus a single logical change
106			is contained within a single patch.
107
108			If one patch depends on another patch in order for a change to be
109			complete, that is OK. Simply note "this patch depends on patch X"
110			in your patch description.
111
112
113			4) Select e-mail destination.
114
115			Look through the MAINTAINERS file and the source code, and determine
116			if your change applies to a specific subsystem of the kernel, with
117			an assigned maintainer. If so, e-mail that person.
118
119			If no maintainer is listed, or the maintainer does not respond, send
120			your patch to the primary Linux kernel developer's mailing list,
121			linux-kernel@vger.kernel.org. Most kernel developers monitor this
122			e-mail list, and can comment on your changes.
123
124			Linus Torvalds is the final arbiter of all changes accepted into the
125			Linux kernel. His e-mail address is <torvalds@osdl.org>. He gets
126			a lot of e-mail, so typically you should do your best to -avoid- sending
127			him e-mail.
128
129			Patches which are bug fixes, are "obvious" changes, or similarly
130			require little discussion should be sent or CC'd to Linus. Patches
131			which require discussion or do not have a clear advantage should
132			usually be sent first to linux-kernel. Only after the patch is
133			discussed should the patch then be submitted to Linus.
134
135			For small patches you may want to CC the Trivial Patch Monkey
136			trivial@rustcorp.com.au set up by Rusty Russell; which collects "trivial"
137			patches. Trivial patches must qualify for one of the following rules:
138			Spelling fixes in documentation
139			Spelling fixes which could break grep(1).
140			Warning fixes (cluttering with useless warnings is bad)
141			Compilation fixes (only if they are actually correct)
142			Runtime fixes (only if they actually fix things)
143			Removing use of deprecated functions/macros (eg. check_region).
144			Contact detail and documentation fixes
145			Non-portable code replaced by portable code (even in arch-specific,
146			since people copy, as long as it's trivial)
147			Any fix by the author/maintainer of the file. (ie. patch monkey
148			in re-transmission mode)
149
150
151
152			5) Select your CC (e-mail carbon copy) list.
153
154			Unless you have a reason NOT to do so, CC linux-kernel@vger.kernel.org.
155
156			Other kernel developers besides Linus need to be aware of your change,
157			so that they may comment on it and offer code review and suggestions.
158			linux-kernel is the primary Linux kernel developer mailing list.
159			Other mailing lists are available for specific subsystems, such as
160			USB, framebuffer devices, the VFS, the SCSI subsystem, etc. See the
161			MAINTAINERS file for a mailing list that relates specifically to
162			your change.
163
164			Even if the maintainer did not respond in step #4, make sure to ALWAYS
165			copy the maintainer when you change their code.
166
167			For small patches you may want to CC the Trivial Patch Monkey
168			trivial@rustcorp.com.au set up by Rusty Russell; which collects "trivial"
169			patches. Trivial patches must qualify for one of the following rules:
170			Spelling fixes in documentation
171			Spelling fixes which could break grep(1).
172			Warning fixes (cluttering with useless warnings is bad)
173			Compilation fixes (only if they are actually correct)
174			Runtime fixes (only if they actually fix things)
175			Removing use of deprecated functions/macros (eg. check_region).
176			Contact detail and documentation fixes
177			Non-portable code replaced by portable code (even in arch-specific,
178			since people copy, as long as it's trivial)
179			Any fix by the author/maintainer of the file. (ie. patch monkey
180			in re-transmission mode)
181
182
183
184			6) No MIME, no links, no compression, no attachments. Just plain text.
185
186			Linus and other kernel developers need to be able to read and comment
187			on the changes you are submitting. It is important for a kernel
188			developer to be able to "quote" your changes, using standard e-mail
189			tools, so that they may comment on specific portions of your code.
190
191			For this reason, all patches should be submitting e-mail "inline".
192			WARNING: Be wary of your editor's word-wrap corrupting your patch,
193			if you choose to cut-n-paste your patch.
194
195			Do not attach the patch as a MIME attachment, compressed or not.
196			Many popular e-mail applications will not always transmit a MIME
197			attachment as plain text, making it impossible to comment on your
198			code. A MIME attachment also takes Linus a bit more time to process,
199			decreasing the likelihood of your MIME-attached change being accepted.
200
201			Exception: If your mailer is mangling patches then someone may ask
202			you to re-send them using MIME.
203
204
205
206			7) E-mail size.
207
208			When sending patches to Linus, always follow step #6.
209
210			Large changes are not appropriate for mailing lists, and some
211			maintainers. If your patch, uncompressed, exceeds 40 kB in size,
212			it is preferred that you store your patch on an Internet-accessible
213			server, and provide instead a URL (link) pointing to your patch.
214
215
216
217			8) Name your kernel version.
218
219			It is important to note, either in the subject line or in the patch
220			description, the kernel version to which this patch applies.
221
222			If the patch does not apply cleanly to the latest kernel version,
223			Linus will not apply it.
224
225
226
227			9) Don't get discouraged. Re-submit.
228
229			After you have submitted your change, be patient and wait. If Linus
230			likes your change and applies it, it will appear in the next version
231			of the kernel that he releases.
232
233			However, if your change doesn't appear in the next version of the
234			kernel, there could be any number of reasons. It's YOUR job to
235			narrow down those reasons, correct what was wrong, and submit your
236			updated change.
237
238			It is quite common for Linus to "drop" your patch without comment.
239			That's the nature of the system. If he drops your patch, it could be
240			due to
241			* Your patch did not apply cleanly to the latest kernel version
242			* Your patch was not sufficiently discussed on linux-kernel.
243			* A style issue (see section 2),
244			* An e-mail formatting issue (re-read this section)
245			* A technical problem with your change
246			* He gets tons of e-mail, and yours got lost in the shuffle
247			* You are being annoying (See Figure 1)
248
249			When in doubt, solicit comments on linux-kernel mailing list.
250
251
252
253			10) Include PATCH in the subject
254
255			Due to high e-mail traffic to Linus, and to linux-kernel, it is common
256			convention to prefix your subject line with [PATCH]. This lets Linus
257			and other kernel developers more easily distinguish patches from other
258			e-mail discussions.
259
260
261
262			11) Sign your work
263
264			To improve tracking of who did what, especially with patches that can
265			percolate to their final resting place in the kernel through several
266			layers of maintainers, we've introduced a "sign-off" procedure on
267			patches that are being emailed around.
268
269			The sign-off is a simple line at the end of the explanation for the
270			patch, which certifies that you wrote it or otherwise have the right to
271			pass it on as a open-source patch. The rules are pretty simple: if you
272			can certify the below:
273
274			Developer's Certificate of Origin 1.1
275
276			By making a contribution to this project, I certify that:
277
278			(a) The contribution was created in whole or in part by me and I
279			have the right to submit it under the open source license
280			indicated in the file; or
281
282			(b) The contribution is based upon previous work that, to the best
283			of my knowledge, is covered under an appropriate open source
284			license and I have the right under that license to submit that
285			work with modifications, whether created in whole or in part
286			by me, under the same open source license (unless I am
287			permitted to submit under a different license), as indicated
288			in the file; or
289
290			(c) The contribution was provided directly to me by some other
291			person who certified (a), (b) or (c) and I have not modified
292			it.
293
294			(d) I understand and agree that this project and the contribution
295			are public and that a record of the contribution (including all
296			personal information I submit with it, including my sign-off) is
297			maintained indefinitely and may be redistributed consistent with
298			this project or the open source license(s) involved.
299
300			then you just add a line saying
301
302			Signed-off-by: Random J Developer <random@developer.org>
303
304			Some people also put extra tags at the end. They'll just be ignored for
305			now, but you can do this to mark internal company procedures or just
306			point out some special detail about the sign-off.
307
308
309			-----------------------------------
310			SECTION 2 - HINTS, TIPS, AND TRICKS
311			-----------------------------------
312
313			This section lists many of the common "rules" associated with code
314			submitted to the kernel. There are always exceptions... but you must
315			have a really good reason for doing so. You could probably call this
316			section Linus Computer Science 101.
317
318
319
320			1) Read Documentation/CodingStyle
321
322			Nuff said. If your code deviates too much from this, it is likely
323			to be rejected without further review, and without comment.
324
325
326
327			2) #ifdefs are ugly
328
329			Code cluttered with ifdefs is difficult to read and maintain. Don't do
330			it. Instead, put your ifdefs in a header, and conditionally define
331			'static inline' functions, or macros, which are used in the code.
332			Let the compiler optimize away the "no-op" case.
333
334			Simple example, of poor code:
335
336			dev = alloc_etherdev (sizeof(struct funky_private));
337			if (!dev)
338			return -ENODEV;
339			#ifdef CONFIG_NET_FUNKINESS
340			init_funky_net(dev);
341			#endif
342
343			Cleaned-up example:
344
345			(in header)
346			#ifndef CONFIG_NET_FUNKINESS
347			static inline void init_funky_net (struct net_device *d) {}
348			#endif
349
350			(in the code itself)
351			dev = alloc_etherdev (sizeof(struct funky_private));
352			if (!dev)
353			return -ENODEV;
354			init_funky_net(dev);
355
356
357
358			3) 'static inline' is better than a macro
359
360			Static inline functions are greatly preferred over macros.
361			They provide type safety, have no length limitations, no formatting
362			limitations, and under gcc they are as cheap as macros.
363
364			Macros should only be used for cases where a static inline is clearly
365			suboptimal [there a few, isolated cases of this in fast paths],
366			or where it is impossible to use a static inline function [such as
367			string-izing].
368
369			'static inline' is preferred over 'static __inline__', 'extern inline',
370			and 'extern __inline__'.
371
372
373
374			4) Don't over-design.
375
376			Don't try to anticipate nebulous future cases which may or may not
377			be useful: "Make it as simple as you can, and no simpler"
378
379
380