bsd.README revision 1.85
1#	$NetBSD: bsd.README,v 1.85 2001/12/28 01:32:40 lukem Exp $
2#	@(#)bsd.README	8.2 (Berkeley) 4/2/94
3
4This is the README file for the new make "include" files for the BSD
5source tree.  The files are installed in /usr/share/mk, and are, by
6convention, named with the suffix ".mk".
7
8Note, this file is not intended to replace reading through the .mk
9files for anything tricky.
10
11=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
12
13RANDOM THINGS WORTH KNOWING:
14
15The files are simply C-style #include files, and pretty much behave like
16you'd expect.  The syntax is slightly different in that a single '.' is
17used instead of the hash mark, i.e. ".include <bsd.prog.mk>".
18
19One difference that will save you lots of debugging time is that inclusion
20of the file is normally done at the *end* of the Makefile.  The reason for
21this is because .mk files often modify variables and behavior based on the
22values of variables set in the Makefile.  To make this work, remember that
23the FIRST target found is the target that is used, i.e. if the Makefile has:
24
25	a:
26		echo a
27	a:
28		echo a number two
29
30the command "make a" will echo "a".  To make things confusing, the SECOND
31variable assignment is the overriding one, i.e. if the Makefile has:
32
33	a=	foo
34	a=	bar
35
36	b:
37		echo ${a}
38
39the command "make b" will echo "bar".  This is for compatibility with the
40way the V7 make behaved.
41
42It's fairly difficult to make the BSD .mk files work when you're building
43multiple programs in a single directory.  It's a lot easier to split up the
44programs than to deal with the problem.  Most of the agony comes from making
45the "obj" directory stuff work right, not because we switched to a new version
46of make.  So, don't get mad at us, figure out a better way to handle multiple
47architectures so we can quit using the symbolic link stuff.  (Imake doesn't
48count.)
49
50The file .depend in the source directory is expected to contain dependencies
51for the source files.  This file is read automatically by make after reading
52the Makefile.
53
54The variable DESTDIR works as before.  It's not set anywhere but will change
55the tree where the file gets installed.
56
57The profiled libraries are no longer built in a different directory than
58the regular libraries.  A new suffix, ".po", is used to denote a profiled
59object, and ".so" denotes a shared (position-independent) object.
60
61The following variables that control how things are made/installed that
62are not set by default. These should not be set by Makefiles; they're for
63the user to define in MAKECONF (see bsd.own.mk, below) or on the make(1)
64command line:
65
66BUILD 		If defined, 'make install' checks that the targets in the
67		source directories are up-to-date and remakes them if they
68                are out of date, instead of blindly trying to install
69                out of date or non-existent targets.
70
71UPDATE 		If defined, 'make install' only installs targets that are
72		more recently modified in the source directories that their
73		installed counterparts.
74
75UNPRIVED	If defined, don't set the owner/group/mode when installing
76		files or directories, and keep a metadata log of what
77		the owner/group/mode should be.  This allows a
78		non-root "make install".
79
80MKCATPAGES	If "no", don't build or install the catman pages.
81
82MKDOC		If "no", don't build or install the documentation.
83
84MKINFO		If "no", don't build or install Info documentation from
85		Texinfo source files.
86
87MKLINT		If "no", don't build or install the lint libraries.
88
89MKMAN		If "no", don't build or install the man or catman pages.
90		Also acts as "MKCATPAGES=no"
91
92MKNLS		If "no", don't build or install the NLS files and locale
93		definition files.
94
95MKOBJ		If "no", don't enable the rule which creates objdirs.
96		"yes" by default.
97
98MKOBJDIRS	If "no", don't create objdirs during a "make build".
99		"no" by default.
100
101MKPIC		If "no", don't build or install shared libraries.
102
103MKPICINSTALL	If "no", don't install the *_pic.a libraries.
104
105MKPROFILE	If "no", don't build or install the profiling libraries.
106
107MKSHARE		If "no", act as "MKCATPAGES=no MKDOC=no MKINFO=no MKMAN=no
108		MKNLS=no".  I.e, don't build catman pages, documentation,
109		Info documentation, man pages, NLS files, ...
110
111=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
112
113The include file <sys.mk> has the default rules for all makes, in the BSD
114environment or otherwise.  You probably don't want to touch this file.
115If you intend to run a cross build, you will need to supply the following
116host tools, and configure the following variables properly:
117
118OBJCOPY		objcopy - copy and translate object files
119
120STRIP		strip - Discard symbols from object files
121
122CONFIG		config - build kernel compilation directories
123
124RPCGEN		rpcgen - Remote Procedure Call (RPC) protocol compiler
125
126MKLOCALE	mklocale - make LC_CTYPE locale files
127
128MTREE		mtree - build directory tree from a spec file
129
130=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
131
132The include file <bsd.man.mk> handles installing manual pages and their
133links.
134
135It has a two targets:
136
137	maninstall:
138		Install the manual page sources and their links.
139	catinstall:
140		Install the preformatted manual pages and their links.
141
142It sets/uses the following variables:
143
144MANDIR		Base path for manual installation.
145
146MANGRP		Manual group.
147
148MANOWN		Manual owner.
149
150MANMODE		Manual mode.
151
152MANSUBDIR	Subdirectory under the manual page section, i.e. "/vax"
153		or "/tahoe" for machine specific manual pages.
154
155MAN		The manual pages to be installed (use a .1 - .9 suffix).
156
157MLINKS		List of manual page links (using a .1 - .9 suffix).  The
158		linked-to file must come first, the linked file second,
159		and there may be multiple pairs.  The files are soft-linked.
160
161The include file <bsd.man.mk> includes a file named "../Makefile.inc" if
162it exists.
163
164=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
165
166The include file <bsd.own.mk> contains source tree configuration parameters,
167such as the owners, groups, etc. for both manual pages and binaries, and
168a few global "feature configuration" parameters.
169
170It has no targets.
171
172To get system-specific configuration parameters, bsd.own.mk will try to
173include the file specified by the "MAKECONF" variable.  If MAKECONF is not
174set, or no such file exists, the system make configuration file, /etc/mk.conf
175is included.  These files may define any of the variables described below.
176
177bsd.own.mk sets the following variables, if they are not already defined
178(defaults are in brackets):
179
180BSDSRCDIR	The real path to the system sources, so that 'make obj'
181		will work correctly. [/usr/src]
182
183BSDOBJDIR	The real path to the system 'obj' tree, so that 'make obj'
184		will work correctly. [/usr/obj]
185
186BINGRP		Binary group. [wheel]
187
188BINOWN		Binary owner. [root]
189
190BINMODE		Binary mode. [555]
191
192NONBINMODE	Mode for non-executable files. [444]
193
194MANDIR		Base path for manual installation. [/usr/share/man/cat]
195
196MANGRP		Manual group. [wheel]
197
198MANOWN		Manual owner. [root]
199
200MANMODE		Manual mode. [${NONBINMODE}]
201
202MANINSTALL	Manual installation type: maninstall, catinstall, or both
203
204LDSTATIC	Control program linking; if set blank, link everything
205		dynamically. If set to "-static", link everything statically.
206		If not set, programs link according to their makefile.
207
208LIBDIR		Base path for library installation. [/usr/lib]
209
210SHLIBDIR	If ${USE_SHLIBDIR} is "yes", use ${SHLIBDIR} instead of
211		${LIBDIR} as the base path for shared library installation.
212		[/usr/lib]
213
214_LIBSODIR	Set to ${SHLIBDIR} if ${USE_SHLIBDIR} is "yes",
215		otherwise set to ${LIBDIR}
216
217SHLINKDIR	Base path for shared linker. [/usr/libexec]
218
219LINTLIBDIR	Base path for lint(1) library installation. [/usr/libdata/lint]
220
221LIBGRP		Library group. [${BINGRP}]
222
223LIBOWN		Library owner. [${BINOWN}]
224
225LIBMODE		Library mode. [${NONBINMODE}]
226
227DOCDIR		Base path for system documentation (e.g. PSD, USD, etc.)
228	        installation. [/usr/share/doc]
229
230HTMLDOCDIR	Base path for html system documentation installation.
231		[/usr/share/doc/html]
232
233DOCGRP		Documentation group. [wheel]
234
235DOCOWN		Documentation owner. [root]
236
237DOCMODE		Documentation mode. [${NONBINMODE}]
238
239NLSDIR		Base path for Native Language Support files installation.
240		[/usr/share/nls]
241
242NLSGRP		Native Language Support files group. [wheel]
243
244NLSOWN		Native Language Support files owner. [root]
245
246NLSMODE		Native Language Support files mode. [${NONBINMODE}]
247
248STRIPFLAG	The flag passed to the install program to cause the binary
249		to be stripped.  This is to be used when building your
250		own install script so that the entire system can be made
251		stripped/not-stripped using a single knob. [-s]
252
253COPY		The flag passed to the install program to cause the binary
254		to be copied rather than moved.  This is to be used when
255		building our own install script so that the entire system
256		can either be installed with copies, or with moves using
257		a single knob. [-c]
258
259Additionally, the following variables may be set by bsd.own.mk or in a
260make configuration file to modify the behaviour of the system build
261process (default values are in brackets along with comments, if set by
262bsd.own.mk):
263
264MKCRYPTO	If set to "no", no cryptography support will be built
265		into the system.  Defaults to "yes".
266
267NOCRYPTO	If set, it is equivalent to setting MKCRYPTO to "no".
268
269MKCRYPTO_IDEA	If set to "yes", IDEA support will be built into
270		libcrypto_idea.a.  Defaults to "no".
271
272MKCRYPTO_RC5	If set to "yes", RC5 support will be built into
273		libcrypto_rc5.a.  Defaults to "no".
274
275MKKERBEROS	If set to "no", disables building Kerberos (v4 or v5)
276		support into various system utilities that support it.
277		Defaults to "yes".  NOTE: This does not affect the
278		building of the Kerberos libraries or infrastructure
279		programs themselves.  To completely disable Kerberos,
280		set MKCRYPTO to "no".
281
282NOKERBEROS	If set, it is equivalent to setting MKKERBEROS to "no".
283
284SKEY		Compile in support for S/key authentication. [yes, set
285		unconditionally]
286
287MANZ		Compress manual pages at installation time.
288
289SYS_INCLUDE	Copy or symlink kernel include files into /usr/include.
290		Possible values are "symlinks" or "copies" (which is
291		the same as the variable being unset).
292
293NOPROFILE	Do not build profiled versions of system libraries
294
295NOPIC		Do not build PIC versions of system libraries, and
296		do not build shared libraries.  [set if ${MACHINE_ARCH}
297		is "sh3" and ${OBJECT_FMT} is "COFF", unset otherwise.]
298
299NOLINT		Do not build lint libraries.
300
301OBJECT_FMT	Object file format. [set to "ELF" on architectures that
302		use ELF -- currently if ${MACHINE_ARCH} is "alpha",
303		"mipsel", "mipseb", "powerpc", "sparc", "sparc64",
304		"i386" and some m68k machines, or set to "a.out" on
305		other architectures].
306
307MKSOFTFLOAT	If "yes", build with options to enable the compiler to
308		generate output containing library calls for floating
309		point and possibly soft-float library support.  Defaults
310		to "no".
311
312bsd.own.mk is generally useful when building your own Makefiles so that
313they use the same default owners etc. as the rest of the tree.
314
315=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
316
317The include file <bsd.prog.mk> handles building programs from one or
318more source files, along with their manual pages.  It has a limited number
319of suffixes, consistent with the current needs of the BSD tree.
320
321It has eight targets:
322
323	all:
324		build the program and its manual page
325	clean:
326		remove the program, any object files and the files a.out,
327		Errs, errs, mklog, and ${PROG}.core.
328	cleandir:
329		remove all of the files removed by the target clean, as
330		well as .depend, tags, and any manual pages.
331		`distclean' is a synonym for `cleandir'.
332	depend:
333		make the dependencies for the source files, and store
334		them in the file .depend.
335	includes:
336		install any header files.
337	install:
338		install the program and its manual pages; if the Makefile
339		does not itself define the target install, the targets
340		beforeinstall and afterinstall may also be used to cause
341		actions immediately before and after the install target
342		is executed.
343	lint:
344		run lint on the source files
345	tags:
346		create a tags file for the source files.
347
348It sets/uses the following variables:
349
350BINGRP		Binary group.
351
352BINOWN		Binary owner.
353
354BINMODE		Binary mode.
355
356CLEANFILES	Additional files to remove for the clean and cleandir targets.
357
358COPTS		Additional flags to the compiler when creating C objects.
359
360CPPFLAGS	Additional flags to the C pre-processor
361
362LDADD		Additional loader objects.  Usually used for libraries.
363		For example, to load with the compatibility and utility
364		libraries, use:
365
366			LDADD+=-lutil -lcompat
367
368LDFLAGS		Additional loader flags.
369
370LINKS		The list of binary links; should be full pathnames, the
371		linked-to file coming first, followed by the linked
372		file.  The files are hard-linked.  For example, to link
373		/bin/test and /bin/[, use:
374
375			LINKS=	${DESTDIR}/bin/test ${DESTDIR}/bin/[
376
377SYMLINKS	The list of symbolic links; should be full pathnames.
378                Syntax is identical to LINKS. Note that DESTDIR is not
379		automatically included in the link.
380
381MAN		Manual pages (should end in .1 - .9).  If no MAN variable is
382		defined, "MAN=${PROG}.1" is assumed.
383
384PROG		The name of the program to build.  If not supplied, nothing
385		is built.
386
387PROGNAME	The name that the above program will be installed as, if
388		different from ${PROG}.
389
390SRCS		List of source files to build the program.  If SRCS is not
391		defined, it's assumed to be ${PROG}.c.
392
393DPADD		Additional dependencies for the program.  Usually used for
394		libraries.  For example, to depend on the compatibility and
395		utility libraries use:
396
397			DPADD+=${LIBCOMPAT} ${LIBUTIL}
398
399		The following libraries are predefined for DPADD:
400
401		LIBCRT0?=	${DESTDIR}/usr/lib/crt0.o
402		LIBC?=		${DESTDIR}/usr/lib/libc.a
403		LIBC_PIC?=	${DESTDIR}/usr/lib/libc_pic.a
404		LIBCOMPAT?=	${DESTDIR}/usr/lib/libcompat.a
405		LIBCRYPT?=	${DESTDIR}/usr/lib/libcrypt.a
406		LIBCURSES?=	${DESTDIR}/usr/lib/libcurses.a
407		LIBDBM?=	${DESTDIR}/usr/lib/libdbm.a
408		LIBDES?=	${DESTDIR}/usr/lib/libdes.a
409		LIBEDIT?=	${DESTDIR}/usr/lib/libedit.a
410		LIBFORM?=	${DESTDIR}/usr/lib/libform.a
411		LIBGCC?=	${DESTDIR}/usr/lib/libgcc.a
412		LIBGNUMALLOC?=	${DESTDIR}/usr/lib/libgnumalloc.a
413		LIBINTL?=	${DESTDIR}/usr/lib/libintl.a
414		LIBIPSEC?=	${DESTDIR}/usr/lib/libipsec.a
415		LIBKDB?=	${DESTDIR}/usr/lib/libkdb.a
416		LIBKRB?=	${DESTDIR}/usr/lib/libkrb.a
417		LIBKVM?=	${DESTDIR}/usr/lib/libkvm.a
418		LIBL?=		${DESTDIR}/usr/lib/libl.a
419		LIBM?=		${DESTDIR}/usr/lib/libm.a
420		LIBMENU?=	${DESTDIR}/usr/lib/libmenu.a
421		LIBMP?=		${DESTDIR}/usr/lib/libmp.a
422		LIBNTP?=	${DESTDIR}/usr/lib/libntp.a
423		LIBPC?=		${DESTDIR}/usr/lib/libpc.a
424		LIBPCAP?=	${DESTDIR}/usr/lib/libpcap.a
425		LIBPLOT?=	${DESTDIR}/usr/lib/libplot.a
426		LIBPOSIX?=	${DESTDIR}/usr/lib/libposix.a
427		LIBRESOLV?=	${DESTDIR}/usr/lib/libresolv.a
428		LIBRPCSVC?=	${DESTDIR}/usr/lib/librpcsvc.a
429		LIBSKEY?=	${DESTDIR}/usr/lib/libskey.a
430		LIBTERMCAP?=	${DESTDIR}/usr/lib/libtermcap.a
431		LIBTELNET?=	${DESTDIR}/usr/lib/libtelnet.a
432		LIBUTIL?=	${DESTDIR}/usr/lib/libutil.a
433		LIBWRAP?=	${DESTDIR}/usr/lib/libwrap.a
434		LIBY?=		${DESTDIR}/usr/lib/liby.a
435		LIBZ?=		${DESTDIR}/usr/lib/libz.a
436
437
438SHAREDSTRINGS	If defined, a new .c.o rule is used that results in shared
439		strings, using xstr(1). Note that this will not work with
440		parallel makes.
441
442STRIPFLAG	The flag passed to the install program to cause the binary
443		to be stripped.
444
445SUBDIR		A list of subdirectories that should be built as well.
446		Each of the targets will execute the same target in the
447		subdirectories.
448
449SCRIPTS		A list of interpreter scripts [file.{sh,csh,pl,awk,...}].
450		These are installed exactly like programs.
451
452SCRIPTSNAME	The name that the above program will be installed as, if
453		different from ${SCRIPTS}. These can be further specialized
454		by setting SCRIPTSNAME_<script>.
455
456FILES		A list of files to install. The installation is controlled
457		by the FILESNAME, FILESOWN, FILESGRP, FILESMODE, FILESDIR
458		variables that can be further specialized by FILES<VAR>_<file>
459
460SHLINKDIR	Target directory for shared linker.
461
462The include file <bsd.prog.mk> includes the file named "../Makefile.inc"
463if it exists, as well as the include file <bsd.man.mk>.
464
465Some simple examples:
466
467To build foo from foo.c with a manual page foo.1, use:
468
469	PROG=	foo
470
471	.include <bsd.prog.mk>
472
473To build foo from foo.c with a manual page foo.2, add the line:
474
475	MAN=	foo.2
476
477If foo does not have a manual page at all, add the line:
478
479	MKMAN=	no
480
481If foo has multiple source files, add the line:
482
483	SRCS=	a.c b.c c.c d.c
484
485=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
486
487The include file <bsd.subdir.mk> contains the default targets for building
488subdirectories.  It has the same eight targets as <bsd.prog.mk>: all, 
489clean, cleandir, depend, includes, install, lint, and tags.  For all of
490the directories listed in the variable SUBDIR, the specified directory 
491will be visited and the target made.  There is also a default target which
492allows the command "make subdir" where subdir is any directory listed in
493the variable SUBDIR.
494
495As a special case, the use of a token .WAIT as an entry in SUBDIR acts
496as a synchronization barrier when multiple make jobs are run; subdirs
497before the .WAIT must complete before any subdirs after .WAIT are
498started.  See make(1) for some caveats on use of .WAIT and other
499special sources.
500
501=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
502
503The include file <bsd.links.mk> handles the LINKS and SYMLINKS variables
504and is included from from bsd.lib.mk and bsd.prog.mk.
505
506=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
507
508The include file <bsd.files.mk> handles the FILES variables and is included
509from bsd.lib.mk and bsd.prog.mk.
510
511=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
512
513The include file <bsd.inc.mk> defines the includes target and uses two
514variables:
515
516INCS		The list of include files
517
518INCSDIR		The location to install the include files.
519
520INCSNAME	Target name of the include file, if only one; same as
521		FILESNAME, but for include files.
522
523INCSNAME_<file>	The name file <file> should be installed as, if not <file>,
524		same as FILESNAME_<file>, but for include files.
525
526=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
527
528The include file <bsd.kinc.mk> defines the many targets (includes,
529subdirectories, etc.), and is used by kernel makefiles to handle
530include file installation.  It is intended to be included alone, by
531kernel Makefiles.  Please see bsd.kinc.mk for more details, and keep
532the documentation in that file up to date.
533
534=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
535
536The include file <bsd.info.mk> is used to generate and install GNU Info
537documentation from respective Texinfo source files.  It defines three
538implicit targets (.txi.info, .texi.info, and .texinfo.info), and uses the
539following variables:
540
541TEXINFO		List of Texinfo source files.  Info documentation will
542		consist of single files with the extension replaced by
543		.info.
544
545INFOFLAGS	Flags to pass to makeinfo.  []
546
547INSTALL_INFO	Name of install-info program.  [install-info]
548
549MAKEINFO	Name of makeinfo program.  [makeinfo]
550
551=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
552
553The include file <bsd.sys.mk> is used by <bsd.prog.mk> and
554<bsd.lib.mk>.  It contains overrides that are used when building
555the NetBSD source tree.  For instance, if "PARALLEL" is defined by
556the program/library Makefile, it includes a set of rules for lex and
557yacc that allow multiple lex and yacc targets to be built in parallel.
558
559Other variables of note (incomplete list):
560
561WARNS		Crank up gcc warning options; the distinct levels are:
562			WARNS=1
563			WARNS=2
564			WARNS=3
565
566FORMAT_AUDIT	If FORMAT_AUDIT is set, and WFORMAT is set and > 1, turn on
567WFORMAT 	-Wnetbsd-format-audit for extra-stringent format checking.
568		WFORMAT belongs in individual makefiles and/or
569		Makefile.inc files.  (set WFORMAT=1 in individual
570		makefiles if a program is not security critical and is
571		doing bizarre things with format strings which would
572		be even uglier if rewritten) FORMAT_AUDIT should go in
573		mk.conf if you're doing format-string auditing. 
574		FORMAT_AUDIT may go away in time.
575
576=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
577
578The include file <bsd.lib.mk> has support for building libraries.  It has
579the same eight targets as <bsd.prog.mk>: all, clean, cleandir, depend,
580includes, install, lint, and tags.  Additionally, it has a checkver target
581which checks for installed shared object libraries whose version is greater
582that the version of the source. It has a limited number of suffixes,
583consistent with the current needs of the BSD tree.
584
585It sets/uses the following variables:
586
587LIB		The name of the library to build.
588
589LIBDIR		Target directory for libraries.
590
591SHLIBDIR	Target directory for shared libraries if ${USE_SHLIBDIR}
592		is "yes".
593
594USE_SHLIBDIR	If "yes", use ${SHLIBDIR} instead of ${LIBDIR}
595		as the path to install shared libraries to.
596
597LINTLIBDIR	Target directory for lint libraries.
598
599LIBGRP		Library group.
600
601LIBOWN		Library owner.
602
603LIBMODE		Library mode.
604
605LDADD		Additional loader objects.
606
607MAN		The manual pages to be installed (use a .1 - .9 suffix).
608
609MKLINKLIB	If "no", act as "MKPICINSTALL=no MKPROFILE=no".
610		Also:
611			- don't install the .a libraries
612			- don't install _pic.a libraries on PIC systems
613			- don't build .a libraries on PIC systems
614			- don't install the .so symlink on ELF systems
615		I.e, only install the shared library (and the .so.major
616		symlink on ELF).
617
618MKPICLIB	If "no", don't build _pic.a libraries, and build the
619		shared object libraries from the .a libraries.  A
620		symlink is installed in ${DESTDIR}/usr/lib for the
621		_pic.a library pointing to the .a library.
622
623NOCHECKVER_<library>
624NOCHECKVER	If set, disables checking for installed shared object
625		libraries with versions greater than the source.  A
626		particular library name, without the "lib" prefix, may
627		be appended to the variable name to disable the check for
628		only that library.
629
630SRCS		List of source files to build the library.  Suffix types
631		.s, .c, and .f are supported.  Note, .s files are preferred
632		to .c files of the same name.  (This is not the default for
633		versions of make.)
634
635The include file <bsd.lib.mk> includes the file named "../Makefile.inc"
636if it exists, as well as the include file <bsd.man.mk>.
637
638It has rules for building profiled objects; profiled libraries are
639built by default.
640
641Libraries are ranlib'd when made.
642
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644
645The include file <bsd.obj.mk> defines targets related to the creation
646and use of separated object and source directories.
647
648If an environment variable named MAKEOBJDIRPREFIX is set, make(1) uses
649${MAKEOBJDIRPREFIX}${.CURDIR} as the name of the object directory if
650it exists.  Otherwise make(1) looks for the existence of a
651subdirectory (or a symlink to a directory) of the source directory
652into which built targets should be placed.  If an environment variable
653named MAKEOBJDIR is set, make(1) uses its value as the name of the
654object directory; failing that, make first looks for a subdirectory
655named "obj.${MACHINE}", and if that doesn't exist, it looks for "obj".
656
657Object directories are not created automatically by make(1) if they
658don't exist; you need to run a separate "make obj".  (This will happen
659during a top-level build if "MKOBJDIRS" is set to a value other than
660"no").  When the source directory is a subdirectory of ${BSDSRCDIR} --
661and this is determined by a simple string prefix comparison -- object
662directories are created in a separate object directory tree, and a
663symlink to the object directory in that tree is created in the source
664directory; otherwise, "make obj" assumes that you're not in the main
665source tree and that it's not safe to use a separate object tree.
666
667Several variables used by <bsd.obj.mk> control exactly what
668directories and links get created during a "make obj":
669
670MAKEOBJDIR	If set, this is the component name of the object
671		directory.
672
673OBJMACHINE	If this is set but MAKEOBJDIR is not set, creates
674		object directories or links named "obj.${MACHINE}";
675		otherwise, just creates ones named "obj".
676
677USR_OBJMACHINE  If set, and the current directory is a subdirectory of
678		${BSDSRCDIR}, create object directory in the
679		corresponding subdirectory of ${BSDOBJDIR}.${MACHINE};
680		otherwise, create it in the corresponding subdirectory
681		of ${BSDOBJDIR}
682
683=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
684
685The include file <bsd.kernobj.mk> defines variables related to the
686location of kernel sources and object directories.
687
688KERNSRCDIR	Is the location of the top of the kernel src.
689		It defaults to ${BSDSRCDIR}/sys, but the top-level
690		Makefile.inc sets it to ${ABSTOP}/sys (ABSTOP is the
691		absolute path to the directory where the top-level
692		Makefile.inc was found.
693
694KERNARCHDIR	Is the location of the machine dependent kernel
695		sources.  It defaults to arch/${MACHINE}
696		
697KERNCONFDIR	Is where the configuration files for kernels are
698		found; default is ${KERNSRCDIR}/${KERNARCHDIR}/conf.
699
700KERNOBJDIR	Is the kernel build directory.  The kernel GENERIC for
701		instance will be compiled in ${KERNOBJDIR}/GENERIC.
702		The default value is
703		${MAKEOBJDIRPREFIX}${KERNSRCDIR}/${KERNARCHDIR}/compile
704		if it exists or the target 'obj' is being made.
705		Otherwise the default is
706		${KERNSRCDIR}/${KERNARCHDIR}/compile.
707
708It is important that Makefiles (such as those under src/distrib) that
709wish to find compiled kernels use bsd.kernobj.mk and ${KERNOBJDIR}
710rather than make assumptions about the location of the compiled kernel.
711
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713