xref: /freebsd/share/mk/bsd.README (revision e14ddd1f16e7e5788392c50de21ea7c927e0690c)
1#	@(#)bsd.README	8.2 (Berkeley) 4/2/94
2# $FreeBSD$
3
4This is the README file for the "include" files for the FreeBSD
5source tree.  The files are installed in /usr/share/mk, and are by
6convention, named with the suffix ".mk".  These files store several
7build options and should be handled with caution.
8
9Note, this file is not intended to replace reading through the .mk
10files for anything tricky.
11
12There are two main types of make include files.  One type is the generally
13usable make include files, such as bsd.prog.mk and bsd.lib.mk.  The other is
14the internal make include files, such as bsd.files.mk and bsd.man.mk, which
15can not/should not be used directly but are used by the other make include
16files.  In most cases it is only interesting to include bsd.prog.mk or
17bsd.lib.mk.
18
19bsd.cpu.mk		- sets CPU/arch-related variables
20bsd.dep.mk		- handle Makefile dependencies
21bsd.doc.mk		- building troff system documents
22bsd.files.mk		- install of general purpose files
23bsd.incs.mk		- install of include files
24bsd.info.mk		- building GNU Info hypertext system
25bsd.init.mk		- initialization for the make include files
26bsd.kmod.mk		- building loadable kernel modules
27bsd.lib.mk		- support for building libraries
28bsd.libnames.mk		- define library names
29bsd.links.mk		- install of links (sym/hard)
30bsd.man.mk		- install of manual pages and their links
31bsd.nls.mk		- build and install of NLS catalogs
32bsd.obj.mk		- creating 'obj' directories and cleaning up
33bsd.own.mk		- define common variables
34bsd.port.mk		- building ports
35bsd.port.post.mk	- building ports
36bsd.port.pre.mk		- building ports
37bsd.port.subdir.mk	- targets for building subdirectories for ports
38bsd.prog.mk		- building programs from source files
39bsd.snmpmod.mk		- building modules for the SNMP daemon bsnmpd
40bsd.subdir.mk		- targets for building subdirectories
41bsd.sys.mk		- common settings used for building FreeBSD sources
42sys.mk			- default rules for all makes
43
44This file does not document bsd.port*.mk.  They are documented in ports(7).
45
46See also make(1), mkdep(1), style.Makefile(5) and `PMake - A
47Tutorial', located in /usr/share/doc/psd/12.make.
48
49=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
50
51Random things worth knowing about this document:
52
53If appropriate when documenting the variables the default value is
54indicated using square brackets e.g. [gzip].
55In some cases the default value depend on other values (e.g. system
56architecture).  In these cases the most common value is indicated.
57
58This document contains some simple examples of the usage of the BSD make
59include files.  For more examples look at the makefiles in the FreeBSD
60source tree.
61
62=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
63
64RANDOM THINGS WORTH KNOWING:
65
66The files are like C-style #include files, and pretty much behave like
67you'd expect.  The syntax is slightly different in that a single '.' is
68used instead of the hash mark, i.e. ".include <bsd.prog.mk>".
69
70One difference that will save you lots of debugging time is that inclusion
71of the file is normally done at the *end* of the Makefile.  The reason for
72this is because .mk files often modify variables and behavior based on the
73values of variables set in the Makefile.  To make this work, remember that
74the FIRST target found is the target that is used, i.e. if the Makefile has:
75
76	a:
77		echo a
78	a:
79		echo a number two
80
81the command "make a" will echo "a".  To make things confusing, the SECOND
82variable assignment is the overriding one, i.e. if the Makefile has:
83
84	a=	foo
85	a=	bar
86
87	b:
88		echo ${a}
89
90the command "make b" will echo "bar".  This is for compatibility with the
91way the V7 make behaved.
92
93It's fairly difficult to make the BSD .mk files work when you're building
94multiple programs in a single directory.  It's a lot easier to split up
95the programs than to deal with the problem.  Most of the agony comes from
96making the "obj" directory stuff work right, not because we switch to a new
97version of make.  So, don't get mad at us, figure out a better way to handle
98multiple architectures so we can quit using the symbolic link stuff.
99(Imake doesn't count.)
100
101The file .depend in the source directory is expected to contain dependencies
102for the source files.  This file is read automatically by make after reading
103the Makefile.
104
105The variable DESTDIR works as before.  It's not set anywhere but will change
106the tree where the file gets installed.
107
108The profiled libraries are no longer built in a different directory than
109the regular libraries.  A new suffix, ".po", is used to denote a profiled
110object.
111
112=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
113
114The include file <sys.mk> has the default rules for all makes, in the BSD
115environment or otherwise.  You probably don't want to touch this file.
116
117=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
118
119The include file <bsd.man.mk> handles installing manual pages and their
120links.
121
122It has three targets:
123
124	all-man:
125		build manual pages.
126	maninstall:
127		install the manual pages and their links.
128	manlint:
129		verify the validity of manual pages.
130
131It sets/uses the following variables:
132
133MANDIR		Base path for manual installation.
134
135MANGRP		Manual group.
136
137MANOWN		Manual owner.
138
139MANMODE		Manual mode.
140
141MANSUBDIR	Subdirectory under the manual page section, i.e. "/vax"
142		or "/tahoe" for machine specific manual pages.
143
144MAN		The manual pages to be installed (use a .1 - .9 suffix).
145
146MLINKS		List of manual page links (using a .1 - .9 suffix).  The
147		linked-to file must come first, the linked file second,
148		and there may be multiple pairs.  The files are soft-linked.
149
150The include file <bsd.man.mk> includes a file named "../Makefile.inc" if
151it exists.
152
153=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
154
155The include file <bsd.own.mk> contains the owners, groups, etc. for both
156manual pages and binaries.
157
158It has no targets.
159
160It sets/uses the following variables:
161
162BINGRP		Binary group.
163
164BINOWN		Binary owner.
165
166BINMODE		Binary mode.
167
168MANDIR		Base path for manual installation.
169
170MANGRP		Manual group.
171
172MANOWN		Manual owner.
173
174MANMODE		Manual mode.
175
176This file is generally useful when building your own Makefiles so that
177they use the same default owners etc. as the rest of the tree.
178
179=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
180
181The include file <bsd.prog.mk> handles building programs from one or
182more source files, along with their manual pages.  It has a limited number
183of suffixes, consistent with the current needs of the BSD tree.
184
185It has seven targets:
186
187	all:
188		build the program and its manual page
189	clean:
190		remove the program and any object files.
191	cleandir:
192		remove all of the files removed by the target clean, as
193		well as .depend, tags, and any manual pages.
194	depend:
195		make the dependencies for the source files, and store
196		them in the file .depend.
197	install:
198		install the program and its manual pages; if the Makefile
199		does not itself define the target install, the targets
200		beforeinstall and afterinstall may also be used to cause
201		actions immediately before and after the install target
202		is executed.
203	lint:
204		run lint on the source files
205	tags:
206		create a tags file for the source files.
207
208It sets/uses the following variables:
209
210BINGRP		Binary group.
211
212BINOWN		Binary owner.
213
214BINMODE		Binary mode.
215
216CLEANFILES	Additional files to remove and
217CLEANDIRS	additional directories to remove during clean and cleandir
218		targets.  "rm -f" and "rm -rf" used respectively.
219
220CFLAGS		Flags to the compiler when creating C objects.
221
222FILES		A list of non-executable files.
223		The installation is controlled by the FILESNAME, FILESOWN,
224		FILESGRP, FILESMODE, FILESDIR variables that can be
225		further specialized by FILES<VAR>_<file>.
226
227LDADD		Additional loader objects.  Usually used for libraries.
228		For example, to load with the compatibility and utility
229		libraries, use:
230
231			LDADD=-lutil -lcompat
232
233LDFLAGS		Additional loader flags.
234
235LINKS		The list of binary links; should be full pathnames, the
236		linked-to file coming first, followed by the linked
237		file.  The files are hard-linked.  For example, to link
238		/bin/test and /bin/[, use:
239
240			LINKS=	${DESTDIR}/bin/test ${DESTDIR}/bin/[
241
242MAN		Manual pages (should end in .1 - .9).  If no MAN variable
243		is defined, "MAN=${PROG}.1" is assumed.
244
245PROG		The name of the program to build.  If not supplied, nothing
246		is built.
247
248PROG_CXX	If defined, the name of the program to build.  Also
249		causes <bsd.prog.mk> to link the program with the
250		standard C++ library.  PROG_CXX overrides the value
251		of PROG if PROG is also set.
252
253PROGNAME	The name that the above program will be installed as, if
254		different from ${PROG}.
255
256SRCS		List of source files to build the program.  If SRCS is not
257		defined, it's assumed to be ${PROG}.c or, if PROG_CXX is
258		defined, ${PROG_CXX}.cc.
259
260DPADD		Additional dependencies for the program.  Usually used for
261		libraries.  For example, to depend on the compatibility and
262		utility libraries use:
263
264			DPADD=${LIBCOMPAT} ${LIBUTIL}
265
266		There is a predefined identifier for each (non-profiled,
267		non-shared) library and object.  Library file names are
268		transformed to identifiers by removing the extension and
269		converting to upper case.
270
271		There are no special identifiers for profiled or shared
272		libraries or objects.  The identifiers for the standard
273		libraries are used in DPADD.  This works correctly iff all
274		the libraries are built at the same time.  Unfortunately,
275		it causes unnecessary relinks to shared libraries when
276		only the static libraries have changed.  Dependencies on
277		shared libraries should be only on the library version
278		numbers.
279
280STRIP		The flag passed to the install program to cause the binary
281		to be stripped.  This is to be used when building your
282		own install script so that the entire system can be made
283		stripped/not-stripped using a single nob.
284
285SUBDIR		A list of subdirectories that should be built as well.
286		Each of the targets will execute the same target in the
287		subdirectories.
288
289SCRIPTS		A list of interpreter scripts [file.{sh,csh,pl,awk,...}].
290		The installation is controlled by the SCRIPTSNAME, SCRIPTSOWN,
291		SCRIPTSGRP, SCRIPTSMODE, SCRIPTSDIR variables that can be
292		further specialized by SCRIPTS<VAR>_<script>.
293
294The include file <bsd.prog.mk> includes the file named "../Makefile.inc"
295if it exists, as well as the include file <bsd.man.mk>.
296
297Some simple examples:
298
299To build foo from foo.c with a manual page foo.1, use:
300
301	PROG=	foo
302
303	.include <bsd.prog.mk>
304
305To build foo from foo.c with a manual page foo.2, add the line:
306
307	MAN=	foo.2
308
309If foo does not have a manual page at all, add the line:
310
311	NO_MAN=
312
313If foo has multiple source files, add the line:
314
315	SRCS=	a.c b.c c.c d.c
316
317=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
318
319The include file <bsd.subdir.mk> contains the default targets for building
320subdirectories.  It has the same seven targets as <bsd.prog.mk>: all, clean,
321cleandir, depend, install, lint, and tags.  For all of the directories
322listed in the variable SUBDIRS, the specified directory will be visited
323and the target made.  There is also a default target which allows the
324command "make subdir" where subdir is any directory listed in the variable
325SUBDIRS.
326
327=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
328
329The include file <bsd.lib.mk> has support for building libraries.  It has
330the same seven targets as <bsd.prog.mk>: all, clean, cleandir, depend,
331install, lint, and tags.  It has a limited number of suffixes, consistent
332with the current needs of the BSD tree.
333
334It sets/uses the following variables:
335
336LIBDIR		Target directory for libraries.
337
338LINTLIBDIR	Target directory for lint libraries.
339
340LIBGRP		Library group.
341
342LIBOWN		Library owner.
343
344LIBMODE		Library mode.
345
346LDADD		Additional loader objects.
347
348MAN		The manual pages to be installed (use a .1 - .9 suffix).
349
350SRCS		List of source files to build the library.  Suffix types
351		.s, .c, and .f are supported.  Note, .s files are preferred
352		to .c files of the same name.  (This is not the default for
353		versions of make.)
354
355SHLIB_LDSCRIPT	Template file to generate shared library linker script.
356		Unless used, a simple symlink is created to the real
357		shared object.
358
359LIBRARIES_ONLY	Do not build or install files other than the library.
360
361The include file <bsd.lib.mk> includes the file named "../Makefile.inc"
362if it exists, as well as the include file <bsd.man.mk>.
363
364It has rules for building profiled objects; profiled libraries are
365built by default.
366
367Libraries are ranlib'd before installation.
368