Add thread-safety to libc, so that libc_r will build (on i386 at least).

All POSIX libc api now there (to P1003.1c/D10)
  (more md stuff is needed for other libc/arch/*)
  (setlogin is no longer a special syscall)
Add -pthread option to gcc (that makes it use -lc_r and -D_POSIX_THREADS).
Doc some re-entrant routines
Add libc_r to intro(3)
dig() uses some libc srcs and an extra -I was needed there.
Add more md stuff to libc_r.
Update includes for the pthreads api
Update libc_r TODO

73 files changed, 1333 insertions, 336 deletions

diff --git a/gnu/usr.bin/gcc/config/openbsd.h b/gnu/usr.bin/gcc/config/openbsd.h
index b59d09cf830..eae7a4a094c 100644
--- a/gnu/usr.bin/gcc/config/openbsd.h
+++ b/gnu/usr.bin/gcc/config/openbsd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: openbsd.h,v 1.9 1998/05/06 14:25:35 csapuntz Exp $	*/
+/*	$OpenBSD: openbsd.h,v 1.10 1998/11/20 11:18:22 d Exp $	*/
 
 /* OPENBSD_NATIVE is defined when gcc is integrated into the OpenBSD
    source tree so it can be configured appropriately when using the
@@ -40,7 +40,7 @@
    the GCC option `-posix'.  */
 
 #undef CPP_SPEC
-#define CPP_SPEC "%{posix:-D_POSIX_SOURCE}"
+#define CPP_SPEC "%{posix:-D_POSIX_SOURCE} %{pthread:-D_POSIX_THREADS}"
 
 /* Provide an ASM_SPEC appropriate for OpenBSD.  Currently we only deal
    with the options for generating PIC code.  */
@@ -50,9 +50,11 @@
 
 /* Provide a LIB_SPEC appropriate for OpenBSD.  Just select the appropriate
    libc, depending on whether we're doing profiling.  */
+/* Also, deal with the -pthread option. */
 
 #undef LIB_SPEC
-#define LIB_SPEC "%{!p:%{!pg:-lc}}%{p:-lc_p}%{pg:-lc_p}"
+/* #define LIB_SPEC "%{!p:%{!pg:-lc}}%{p:-lc_p}%{pg:-lc_p}" */
+#define LIB_SPEC "-lc%{pthread:_r}%{p:_p}%{!p:%{pg:_p}}"
 
 /* Provide a LINK_SPEC appropriate for OpenBSD.  Here we provide support
    for the special GCC options -static, -assert, and -nostdlib.  */
diff --git a/include/dirent.h b/include/dirent.h
index 3962c412c04..6023a5db842 100644
--- a/include/dirent.h
+++ b/include/dirent.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: dirent.h,v 1.3 1997/09/21 10:45:30 niklas Exp $	*/
+/*	$OpenBSD: dirent.h,v 1.4 1998/11/20 11:18:25 d Exp $	*/
 /*	$NetBSD: dirent.h,v 1.9 1995/03/26 20:13:37 jtc Exp $	*/
 
 /*-
@@ -105,6 +105,7 @@ int scandir __P((const char *, struct dirent ***,
 int alphasort __P((const void *, const void *));
 int getdirentries __P((int, char *, int, long *));
 #endif /* not POSIX */
+int readdir_r __P((DIR *, struct dirent *, struct dirent **));
 __END_DECLS
 
 #endif /* !_KERNEL */
diff --git a/include/limits.h b/include/limits.h
index f9998eb748b..772688e8204 100644
--- a/include/limits.h
+++ b/include/limits.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: limits.h,v 1.5 1998/07/11 06:02:44 deraadt Exp $	*/
+/*	$OpenBSD: limits.h,v 1.6 1998/11/20 11:18:25 d Exp $	*/
 /*	$NetBSD: limits.h,v 1.7 1994/10/26 00:56:00 cgd Exp $	*/
 
 /*
@@ -63,6 +63,10 @@
 #define	_POSIX2_LINE_MAX	2048
 #define	_POSIX2_RE_DUP_MAX	255
 
+/* P1003.1c */
+#define _POSIX_TTY_NAME_MAX	260
+#define _POSIX_LOGIN_NAME_MAX	MAXLOGNAME
+
 #if !defined(_POSIX_C_SOURCE) || defined(_XOPEN_SOURCE)
 #define PASS_MAX		128
 
@@ -78,6 +82,10 @@
 
 #endif /* !_ANSI_SOURCE */
 
+/* where does this belong? it is defined by P1003.1c */
+#define TTY_NAME_MAX		_POSIX_TTY_NAME_MAX
+#define LOGIN_NAME_MAX		MAXLOGNAME
+
 #include <machine/limits.h>
 #include <sys/syslimits.h>
 
diff --git a/include/signal.h b/include/signal.h
index c2ab6cd8382..82f39b14f11 100644
--- a/include/signal.h
+++ b/include/signal.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: signal.h,v 1.3 1996/09/20 07:27:50 deraadt Exp $	*/
+/*	$OpenBSD: signal.h,v 1.4 1998/11/20 11:18:26 d Exp $	*/
 /*	$NetBSD: signal.h,v 1.8 1996/02/29 00:04:57 jtc Exp $	*/
 
 /*-
@@ -113,6 +113,7 @@ int	sigstack __P((const struct sigstack *, struct sigstack *));
 int	sigaltstack __P((const struct sigaltstack *, struct sigaltstack *));
 int	sigvec __P((int, struct sigvec *, struct sigvec *));
 void	psignal __P((unsigned int, const char *));
+int	sigwait __P((const sigset_t *, int *));
 #endif	/* !_POSIX_SOURCE */
 #endif	/* !_ANSI_SOURCE */
 __END_DECLS
diff --git a/include/stdio.h b/include/stdio.h
index 3458c67809c..ed1fb32c7dd 100644
--- a/include/stdio.h
+++ b/include/stdio.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: stdio.h,v 1.9 1997/11/29 20:01:03 millert Exp $	*/
+/*	$OpenBSD: stdio.h,v 1.10 1998/11/20 11:18:26 d Exp $	*/
 /*	$NetBSD: stdio.h,v 1.18 1996/04/25 18:29:21 jtc Exp $	*/
 
 /*-
@@ -271,10 +271,31 @@ __END_DECLS
 
 __BEGIN_DECLS
 char	*ctermid __P((char *));
+char	*ctermid_r __P((char *));
 char	*cuserid __P((char *));
 FILE	*fdopen __P((int, const char *));
 int	 fileno __P((FILE *));
+void	 flockfile __P((FILE *));
+int	 ftrylockfile __P((FILE *));
+void	 funlockfile __P((FILE *));
+void	 _flockfile_debug __P((FILE *, const char *, int));
+int	 getc_unlocked __P((FILE *));
+int	 putc_unlocked __P((int, FILE *));
+int	 getchar_unlocked __P((void));
+int	 putchar_unlocked __P((int));
 __END_DECLS
+
+#ifndef _POSIX_THREADS
+#  define flockfile(fp)			/* nothing */
+#  define ftrylockfile(fp)		(0)
+#  define funlockfile(fp)		/* nothing */
+#  define _flockfile_debug(fp,f,l)	/* nothing */
+#endif
+
+#if 0 /* defined(DEBUG_FLOCKFILE) && defined(_POSIX_THREADS) */
+#  define flockfile(fp)		_flockfile_debug(fp, __FILE__, __LINE__)
+#endif
+
 #endif /* not ANSI */
 
 /*
@@ -368,23 +389,35 @@ static __inline int __sputc(int _c, FILE *_p) {
 
 #define	feof(p)		__sfeof(p)
 #define	ferror(p)	__sferror(p)
+
+#ifndef _POSIX_THREADS
 #define	clearerr(p)	__sclearerr(p)
+#endif
 
 #ifndef _ANSI_SOURCE
 #define	fileno(p)	__sfileno(p)
 #endif
 
 #ifndef lint
+#ifndef _POSIX_THREADS
 #define	getc(fp)	__sgetc(fp)
+#endif /* _POSIX_THREADS */
+#define	getc_unlocked(fp)	__sgetc(fp)
 /*
- * The macro implementation of putc is not fully POSIX
- * compliant; it does not set errno on failure
+ * The macro implementations of putc and putc_unlocked are not
+ * fully POSIX compliant; they do not set errno on failure
  */
 #ifndef _POSIX_SOURCE
+#ifndef _POSIX_THREADS
 #define putc(x, fp)	__sputc(x, fp)
+#endif /* _POSIX_THREADS */
+#define putc_unlocked(x, fp)	__sputc(x, fp)
 #endif /* _POSIX_SOURCE */
 #endif /* lint */
 
 #define	getchar()	getc(stdin)
 #define	putchar(x)	putc(x, stdout)
+#define getchar_unlocked()	getc_unlocked(stdin)
+#define putchar_unlocked(c)	putc_unlocked(c, stdout)
+
 #endif /* _STDIO_H_ */
diff --git a/include/stdlib.h b/include/stdlib.h
index 39aae35f44d..85e0da154fd 100644
--- a/include/stdlib.h
+++ b/include/stdlib.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: stdlib.h,v 1.7 1998/02/07 02:16:26 millert Exp $	*/
+/*	$OpenBSD: stdlib.h,v 1.8 1998/11/20 11:18:26 d Exp $	*/
 /*	$NetBSD: stdlib.h,v 1.25 1995/12/27 21:19:08 jtc Exp $	*/
 
 /*-
@@ -105,6 +105,7 @@ void	*malloc __P((size_t));
 void	 qsort __P((void *, size_t, size_t,
 	    int (*)(const void *, const void *)));
 int	 rand __P((void));
+int	 rand_r __P((unsigned int *));
 void	*realloc __P((void *, size_t));
 void	 srand __P((unsigned));
 double	 strtod __P((const char *, char **));
diff --git a/include/string.h b/include/string.h
index 42a2e1a4fc9..d170174f80e 100644
--- a/include/string.h
+++ b/include/string.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: string.h,v 1.4 1998/11/04 19:35:48 millert Exp $	*/
+/*	$OpenBSD: string.h,v 1.5 1998/11/20 11:18:26 d Exp $	*/
 /*	$NetBSD: string.h,v 1.6 1994/10/26 00:56:30 cgd Exp $	*/
 
 /*-
@@ -73,6 +73,7 @@ char	*strrchr __P((const char *, int));
 size_t	 strspn __P((const char *, const char *));
 char	*strstr __P((const char *, const char *));
 char	*strtok __P((char *, const char *));
+char	*strtok_r __P((char *, const char *, char **));
 size_t	 strxfrm __P((char *, const char *, size_t));
 
 /* Nonstandard routines */
diff --git a/include/time.h b/include/time.h
index 75cb1c52a75..88a1658afdc 100644
--- a/include/time.h
+++ b/include/time.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: time.h,v 1.3 1998/02/08 18:50:05 deraadt Exp $	*/
+/*	$OpenBSD: time.h,v 1.4 1998/11/20 11:18:26 d Exp $	*/
 /*	$NetBSD: time.h,v 1.9 1994/10/26 00:56:35 cgd Exp $	*/
 
 /*
@@ -95,6 +95,10 @@ time_t mktime __P((struct tm *));
 size_t strftime __P((char *, size_t, const char *, const struct tm *));
 char *strptime __P((const char *, const char *, struct tm *));
 time_t time __P((time_t *));
+char *asctime_r __P((const struct tm *, char *));
+char *ctime_r __P((const time_t *, char *));
+struct tm *gmtime_r __P((const time_t *, struct tm *));
+struct tm *localtime_r __P((const time_t *, struct tm *));
 
 #if !defined(_ANSI_SOURCE)
 #define CLK_TCK		100
diff --git a/include/unistd.h b/include/unistd.h
index 7a43d447438..57f9bc53e1d 100644
--- a/include/unistd.h
+++ b/include/unistd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: unistd.h,v 1.23 1998/11/19 06:44:07 deraadt Exp $ */
+/*	$OpenBSD: unistd.h,v 1.24 1998/11/20 11:18:26 d Exp $ */
 /*	$NetBSD: unistd.h,v 1.26.4.1 1996/05/28 02:31:51 mrg Exp $	*/
 
 /*-
@@ -76,6 +76,7 @@ uid_t	 geteuid __P((void));
 gid_t	 getgid __P((void));
 int	 getgroups __P((int, gid_t *));
 char	*getlogin __P((void));
+int	 getlogin_r __P((char *, size_t));
 pid_t	 getpgrp __P((void));
 pid_t	 getpid __P((void));
 pid_t	 getpgid __P((pid_t));
@@ -98,6 +99,7 @@ long	 sysconf __P((int));
 pid_t	 tcgetpgrp __P((int));
 int	 tcsetpgrp __P((int, pid_t));
 char	*ttyname __P((int));
+int	 ttyname_r __P((int, char *, size_t));
 int	 unlink __P((const char *));
 ssize_t	 write __P((int, const void *, size_t));
 
diff --git a/lib/libc/Makefile b/lib/libc/Makefile
index 0a073cad566..111a7a6138a 100644
--- a/lib/libc/Makefile
+++ b/lib/libc/Makefile
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile,v 1.15 1998/08/08 04:12:16 form Exp $
+#	$OpenBSD: Makefile,v 1.16 1998/11/20 11:18:28 d Exp $
 #
 # All library objects contain sccsid strings by default; they may be
 # excluded as a space-saving measure.  To produce a library that does
@@ -16,61 +16,14 @@
 .include <bsd.own.mk>
 
 LIB=c
-CFLAGS+=-DNLS -DLIBC_SCCS -DSYSLIBC_SCCS -I${.CURDIR}/include
-.if (${YP} == "yes")
-CFLAGS+=-DYP -I${.CURDIR}/yp
-.endif
 LINTFLAGS=-z
-LLIBS=
-AINC=	-I${.CURDIR}/arch/${MACHINE_ARCH}
-.if defined(DESTDIR)
-AINC+=	-nostdinc -idirafter ${DESTDIR}/usr/include
-.endif
 CLEANFILES+=tags
 
-.if exists (${.CURDIR}/arch/${MACHINE_ARCH}/Makefile.inc)
-.PATH:	${.CURDIR}/arch/${MACHINE_ARCH}
-.include "${.CURDIR}/arch/${MACHINE_ARCH}/Makefile.inc"
-.endif
-
-.include "${.CURDIR}/db/Makefile.inc"
-.include "${.CURDIR}/compat-43/Makefile.inc"
-.include "${.CURDIR}/gen/Makefile.inc"
-.include "${.CURDIR}/crypt/Makefile.inc"
-.include "${.CURDIR}/gmon/Makefile.inc"
-.include "${.CURDIR}/hash/Makefile.inc"
-.include "${.CURDIR}/locale/Makefile.inc"
-.include "${.CURDIR}/md/Makefile.inc"
-.include "${.CURDIR}/net/Makefile.inc"
-.include "${.CURDIR}/nls/Makefile.inc"
-.if (${MACHINE_ARCH} != "alpha")
-.include "${.CURDIR}/quad/Makefile.inc"
-.endif
-.include "${.CURDIR}/regex/Makefile.inc"
-.include "${.CURDIR}/rpc/Makefile.inc"
-.include "${.CURDIR}/stdio/Makefile.inc"
-.include "${.CURDIR}/stdlib/Makefile.inc"
-.include "${.CURDIR}/string/Makefile.inc"
-.include "${.CURDIR}/termios/Makefile.inc"
-.include "${.CURDIR}/time/Makefile.inc"
-.include "${.CURDIR}/sys/Makefile.inc"
-.if (${YP} == "yes")
-.include "${.CURDIR}/yp/Makefile.inc"
-.endif
+LIBCSRCDIR=${.CURDIR}
+.include "${LIBCSRCDIR}/Makefile.inc"
 
 NLS=	C.msg Pig.msg de.msg es.msg fi.msg fr.msg nl.msg no.msg ru.msg sv.msg
 
-LIBKERN=	${.CURDIR}/../../sys/lib/libkern
-
-KSRCS=	bcmp.c bzero.c ffs.c strcat.c strcmp.c strcpy.c strlen.c strncmp.c \
-	strncpy.c htonl.c htons.c ntohl.c ntohs.c
-.if (${MACHINE_ARCH} != "alpha")
-KSRCS+=	adddi3.c anddi3.c ashldi3.c ashrdi3.c cmpdi2.c divdi3.c iordi3.c \
-	lshldi3.c lshrdi3.c moddi3.c muldi3.c negdi2.c notdi2.c qdivrem.c \
-	subdi3.c  ucmpdi2.c udivdi3.c umoddi3.c xordi3.c
-KINCLUDES+=	quad/quad.h
-.endif
-
 copy-to-libkern:	copy-to-libkern-machind copy-to-libkern-machdep
 
 copy-to-libkern-machind: ${KSRCS}
@@ -102,6 +55,6 @@ tags: ${SRCS}
 
 beforeinstall:
 	${INSTALL} ${INSTALL_COPY} -o ${BINOWN} -g ${BINGRP} -m 444 tags \
-		${DESTDIR}/var/db/libc.tags
+		${DESTDIR}/var/db/lib${LIB}.tags
 
 .include <bsd.lib.mk>
diff --git a/lib/libc/Makefile.inc b/lib/libc/Makefile.inc
new file mode 100644
index 00000000000..0d224d8fcfc
--- /dev/null
+++ b/lib/libc/Makefile.inc
@@ -0,0 +1,65 @@
+#	$OpenBSD: Makefile.inc,v 1.1 1998/11/20 11:18:28 d Exp $
+#
+# This file contains make rules that are shared by libc and libc_r.
+#
+
+.ifndef LIBCSRCDIR
+all:
+	@echo "need to define LIBCSRCDIR" >&2; exit 1
+.endif
+
+CFLAGS+=	-DLIBC_SCCS -DSYSLIBC_SCCS -I${LIBCSRCDIR}/include
+
+.if (${YP} == "yes")
+CFLAGS+=-DYP -I${LIBCSRCDIR}/yp
+.endif
+
+LLIBS=
+AINC=   -I${LIBCSRCDIR}/arch/${MACHINE_ARCH}
+.if defined(DESTDIR)
+AINC+=  -nostdinc -idirafter ${DESTDIR}/usr/include
+.endif
+
+.if exists (${LIBCSRCDIR}/arch/${MACHINE_ARCH}/Makefile.inc)
+.PATH:	${LIBCSRCDIR}/arch/${MACHINE_ARCH}
+.include "${LIBCSRCDIR}/arch/${MACHINE_ARCH}/Makefile.inc"
+.endif
+
+.include "${LIBCSRCDIR}/db/Makefile.inc"
+.include "${LIBCSRCDIR}/compat-43/Makefile.inc"
+.include "${LIBCSRCDIR}/gen/Makefile.inc"
+.include "${LIBCSRCDIR}/crypt/Makefile.inc"
+.include "${LIBCSRCDIR}/gmon/Makefile.inc"
+.include "${LIBCSRCDIR}/hash/Makefile.inc"
+.include "${LIBCSRCDIR}/locale/Makefile.inc"
+.include "${LIBCSRCDIR}/md/Makefile.inc"
+.include "${LIBCSRCDIR}/net/Makefile.inc"
+.include "${LIBCSRCDIR}/nls/Makefile.inc"
+.if (${MACHINE_ARCH} != "alpha")
+.include "${LIBCSRCDIR}/quad/Makefile.inc"
+.endif
+.include "${LIBCSRCDIR}/regex/Makefile.inc"
+.include "${LIBCSRCDIR}/rpc/Makefile.inc"
+.include "${LIBCSRCDIR}/stdio/Makefile.inc"
+.include "${LIBCSRCDIR}/stdlib/Makefile.inc"
+.include "${LIBCSRCDIR}/string/Makefile.inc"
+.include "${LIBCSRCDIR}/termios/Makefile.inc"
+.include "${LIBCSRCDIR}/time/Makefile.inc"
+.include "${LIBCSRCDIR}/sys/Makefile.inc"
+.if (${YP} == "yes")
+.include "${LIBCSRCDIR}/yp/Makefile.inc"
+.endif
+
+CFLAGS+=-DNLS
+
+LIBKERN=	${LIBCSRCDIR}/../../sys/lib/libkern
+
+KSRCS=	bcmp.c bzero.c ffs.c strcat.c strcmp.c strcpy.c strlen.c strncmp.c \
+	strncpy.c htonl.c htons.c ntohl.c ntohs.c
+.if (${MACHINE_ARCH} != "alpha")
+KSRCS+=	adddi3.c anddi3.c ashldi3.c ashrdi3.c cmpdi2.c divdi3.c iordi3.c \
+	lshldi3.c lshrdi3.c moddi3.c muldi3.c negdi2.c notdi2.c qdivrem.c \
+	subdi3.c  ucmpdi2.c udivdi3.c umoddi3.c xordi3.c
+KINCLUDES+=	quad/quad.h
+.endif
+
diff --git a/lib/libc/arch/i386/SYS.h b/lib/libc/arch/i386/SYS.h
index 1cf818fd304..e02d5cf985f 100644
--- a/lib/libc/arch/i386/SYS.h
+++ b/lib/libc/arch/i386/SYS.h
@@ -33,24 +33,80 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	$OpenBSD: SYS.h,v 1.3 1996/08/19 08:12:12 tholo Exp $
+ *	$OpenBSD: SYS.h,v 1.4 1998/11/20 11:18:29 d Exp $
  */
 
 #include <machine/asm.h>
 #include <sys/syscall.h>
 
 #ifdef __STDC__
+# define    __ENTRY(p,x)	ENTRY(p##x)
+# define    __DO_SYSCALL(x)				\
+				movl $(SYS_##x),%eax;	\
+				int $0x80
+# define    __LABEL2(p,x)	_C_LABEL(p##x)
+#else
+# define    __ENTRY(p,x)	ENTRY(p/**/x)
+# define    __DO_SYSCALL(x)				\
+				movl $(SYS_/**/x),%eax;	\
+				int $0x80
+# define    __LABEL2(p,x)	_C_LABEL(p/**/x)
+#endif
 
-#define	SYSCALL(x)	.text; .align 2; 2: jmp PIC_PLT(cerror); ENTRY(x); movl $(SYS_ ## x),%eax; int $0x80; jc 2b
-#define	RSYSCALL(x)	SYSCALL(x); ret
-#define	PSEUDO(x,y)	ENTRY(x); movl $(SYS_ ## y),%eax; int $0x80; ret
+/* perform a syscall, set errno */
+#define	    __SYSCALL(p,x)				\
+			.text;				\
+			.align 2;			\
+		2:					\
+			jmp PIC_PLT(cerror);		\
+		__ENTRY(p,x);				\
+			__DO_SYSCALL(x);		\
+			jc 2b
 
-#else /* !__STDC__ */
+/* perform a syscall, set errno, return */
+# define    __RSYSCALL(p,x)	__SYSCALL(p,x); ret
 
-#define	SYSCALL(x)	.text; .align 2; 2: jmp PIC_PLT(cerror); ENTRY(x); movl $(SYS_/**/x),%eax; int $0x80; jc 2b
-#define	RSYSCALL(x)	SYSCALL(x); ret
-#define	PSEUDO(x,y)	ENTRY(x); movl $(SYS_/**/y),%eax; int $0x80; ret
+/* perform a syscall, return */
+# define    __PSEUDO(p,x,y)				\
+		__ENTRY(p,x);				\
+			__DO_SYSCALL(y);		\
+			ret
 
-#endif
+/* jump to the real syscall */
+/* XXX shouldn't be here */
+# define    __PASSTHRU(p,x)				\
+			.globl __LABEL2(p,x);		\
+		ENTRY(x);				\
+			jmp PIC_PLT(__LABEL2(p,x))
 
+/*
+ * Design note:
+ *
+ * When the syscalls need to be renamed so they can be handled
+ * specially by the threaded library, these macros insert `_thread_sys_'
+ * in front of their name. This avoids the need to #ifdef _THREAD_SAFE 
+ * everywhere that the renamed function needs to be called.
+ * The PASSTHRU macro is later used for system calls that don't need
+ * wrapping. (XXX its a shame the loader can't do this aliasing)
+ */
+#ifdef _THREAD_SAFE
+/*
+ * For the thread_safe versions, we prepend _thread_sys_ to the function
+ * name so that the 'C' wrapper can go around the real name.
+ */
+# define SYSCALL(x)	__SYSCALL(_thread_sys_,x)
+# define RSYSCALL(x)	__RSYSCALL(_thread_sys_,x)
+# define PSEUDO(x,y)	__PSEUDO(_thread_sys_,x,y)
+# define SYSENTRY(x)	__ENTRY(_thread_sys_,x)
+# define PASSTHRU(x)	__PASSTHRU(_thread_sys_,x)
+#else _THREAD_SAFE
+/*
+ * The non-threaded library defaults to traditional syscalls where
+ * the function name matches the syscall name.
+ */
+# define SYSCALL(x)	__SYSCALL(,x)
+# define RSYSCALL(x)	__RSYSCALL(,x)
+# define PSEUDO(x,y)	__PSEUDO(,x,y)
+# define SYSENTRY(x)	__ENTRY(,x)
+#endif _THREAD_SAFE
 	.globl	cerror
diff --git a/lib/libc/arch/i386/sys/Ovfork.S b/lib/libc/arch/i386/sys/Ovfork.S
index 97430e6ae5f..264e09e302f 100644
--- a/lib/libc/arch/i386/sys/Ovfork.S
+++ b/lib/libc/arch/i386/sys/Ovfork.S
@@ -38,7 +38,7 @@
 
 #if defined(SYSLIBC_SCCS)
 	.text
-	.asciz "$OpenBSD: Ovfork.S,v 1.2 1996/08/19 08:13:26 tholo Exp $"
+	.asciz "$OpenBSD: Ovfork.S,v 1.3 1998/11/20 11:18:29 d Exp $"
 #endif /* SYSLIB_SCCS */
 
 /*
@@ -48,7 +48,7 @@
  * %eax == pid of child in parent, %eax == pid of parent in child.
  *
  */
-ENTRY(vfork)
+SYSENTRY(vfork)
 	popl	%ecx		/* my rta into ecx */
 	movl	$(SYS_vfork),%eax
 	int	$0x80
diff --git a/lib/libc/arch/i386/sys/sigprocmask.S b/lib/libc/arch/i386/sys/sigprocmask.S
index 17853ed793d..ee3d19b7d87 100644
--- a/lib/libc/arch/i386/sys/sigprocmask.S
+++ b/lib/libc/arch/i386/sys/sigprocmask.S
@@ -38,10 +38,10 @@
 
 #if defined(SYSLIBC_SCCS)
 	.text
-	.asciz "$OpenBSD: sigprocmask.S,v 1.3 1997/07/23 20:55:23 kstailey Exp $"
+	.asciz "$OpenBSD: sigprocmask.S,v 1.4 1998/11/20 11:18:30 d Exp $"
 #endif /* SYSLIBC_SCCS */
 
-ENTRY(sigprocmask)
+SYSENTRY(sigprocmask)
 	movl	8(%esp),%ecx		# fetch new sigset pointer
 	testl	%ecx,%ecx		# check new sigset pointer
 	jnz	1f			# if not null, indirect
diff --git a/lib/libc/arch/i386/sys/sigsuspend.S b/lib/libc/arch/i386/sys/sigsuspend.S
index c0254cfebbf..f0c84ce734c 100644
--- a/lib/libc/arch/i386/sys/sigsuspend.S
+++ b/lib/libc/arch/i386/sys/sigsuspend.S
@@ -38,10 +38,10 @@
 
 #if defined(SYSLIBC_SCCS)
 	.text
-	.asciz "$OpenBSD: sigsuspend.S,v 1.2 1996/08/19 08:13:44 tholo Exp $"
+	.asciz "$OpenBSD: sigsuspend.S,v 1.3 1998/11/20 11:18:30 d Exp $"
 #endif /* SYSLIBC_SCCS */
 
-ENTRY(sigsuspend)
+SYSENTRY(sigsuspend)
 	movl	4(%esp),%eax		# fetch mask arg
 	movl	(%eax),%eax		# indirect to mask arg
 	movl	%eax,4(%esp)
diff --git a/lib/libc/arch/i386/sys/syscall.S b/lib/libc/arch/i386/sys/syscall.S
index 4a6db63c799..6ecd61cd4ed 100644
--- a/lib/libc/arch/i386/sys/syscall.S
+++ b/lib/libc/arch/i386/sys/syscall.S
@@ -38,10 +38,10 @@
 
 #if defined(SYSLIBC_SCCS)
 	.text
-	.asciz "$OpenBSD: syscall.S,v 1.2 1996/08/19 08:13:46 tholo Exp $"
+	.asciz "$OpenBSD: syscall.S,v 1.3 1998/11/20 11:18:30 d Exp $"
 #endif /* SYSLIBC_SCCS */
 
-ENTRY(syscall)
+SYSENTRY(syscall)
 	pop	%ecx	/* rta */
 	pop	%eax	/* syscall number */
 	push	%ecx
diff --git a/lib/libc/compat-43/Makefile.inc b/lib/libc/compat-43/Makefile.inc
index e59a1b9fb2c..373e7f4ca4b 100644
--- a/lib/libc/compat-43/Makefile.inc
+++ b/lib/libc/compat-43/Makefile.inc
@@ -1,7 +1,7 @@
-#	$OpenBSD: Makefile.inc,v 1.2 1996/08/19 08:19:13 tholo Exp $
+#	$OpenBSD: Makefile.inc,v 1.3 1998/11/20 11:18:32 d Exp $
 
 # compat-43 sources
-.PATH: ${.CURDIR}/arch/${MACHINE_ARCH}/compat-43 ${.CURDIR}/compat-43
+.PATH: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/compat-43 ${LIBCSRCDIR}/compat-43
 
 SRCS+=	__setreuid.c __setregid.c creat.c getdtablesize.c gethostid.c \
 	getwd.c killpg.c sethostid.c setpgrp.c setregid.c setreuid.c \
diff --git a/lib/libc/crypt/Makefile.inc b/lib/libc/crypt/Makefile.inc
index 9d96d657dbe..8364da1e6e8 100644
--- a/lib/libc/crypt/Makefile.inc
+++ b/lib/libc/crypt/Makefile.inc
@@ -1,6 +1,6 @@
-#	$OpenBSD: Makefile.inc,v 1.10 1998/07/21 22:23:20 provos Exp $
+#	$OpenBSD: Makefile.inc,v 1.11 1998/11/20 11:18:33 d Exp $
 
-.PATH: ${.CURDIR}/arch/${MACHINE_ARCH}/crypt ${.CURDIR}/crypt
+.PATH: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/crypt ${LIBCSRCDIR}/crypt
 
 SRCS+=	cast.c crypt.c morecrypt.c md5crypt.c arc4random.c blowfish.c
 SRCS+=  bcrypt.c
diff --git a/lib/libc/db/Makefile.inc b/lib/libc/db/Makefile.inc
index 44b5a0b1ee6..9f9a35830d4 100644
--- a/lib/libc/db/Makefile.inc
+++ b/lib/libc/db/Makefile.inc
@@ -1,10 +1,10 @@
-#	$OpenBSD: Makefile.inc,v 1.2 1996/08/19 08:19:54 tholo Exp $
+#	$OpenBSD: Makefile.inc,v 1.3 1998/11/20 11:18:33 d Exp $
 #
 CFLAGS+=-D__DBINTERFACE_PRIVATE
 
-.include "${.CURDIR}/db/btree/Makefile.inc"
-.include "${.CURDIR}/db/db/Makefile.inc"
-.include "${.CURDIR}/db/hash/Makefile.inc"
-.include "${.CURDIR}/db/man/Makefile.inc"
-.include "${.CURDIR}/db/mpool/Makefile.inc"
-.include "${.CURDIR}/db/recno/Makefile.inc"
+.include "${LIBCSRCDIR}/db/btree/Makefile.inc"
+.include "${LIBCSRCDIR}/db/db/Makefile.inc"
+.include "${LIBCSRCDIR}/db/hash/Makefile.inc"
+.include "${LIBCSRCDIR}/db/man/Makefile.inc"
+.include "${LIBCSRCDIR}/db/mpool/Makefile.inc"
+.include "${LIBCSRCDIR}/db/recno/Makefile.inc"
diff --git a/lib/libc/db/btree/Makefile.inc b/lib/libc/db/btree/Makefile.inc
index c882f6f7932..ac2f83a919e 100644
--- a/lib/libc/db/btree/Makefile.inc
+++ b/lib/libc/db/btree/Makefile.inc
@@ -1,6 +1,6 @@
-#	$OpenBSD: Makefile.inc,v 1.3 1996/08/19 08:20:00 tholo Exp $
+#	$OpenBSD: Makefile.inc,v 1.4 1998/11/20 11:18:34 d Exp $
 
-.PATH: ${.CURDIR}/db/btree
+.PATH: ${LIBCSRCDIR}/db/btree
 
 SRCS+=	bt_close.c bt_conv.c bt_debug.c bt_delete.c bt_get.c bt_open.c \
 	bt_overflow.c bt_page.c bt_put.c bt_search.c bt_seq.c bt_split.c \
diff --git a/lib/libc/db/db/Makefile.inc b/lib/libc/db/db/Makefile.inc
index c671521a627..d93f931be9b 100644
--- a/lib/libc/db/db/Makefile.inc
+++ b/lib/libc/db/db/Makefile.inc
@@ -1,5 +1,5 @@
-#	$OpenBSD: Makefile.inc,v 1.2 1996/08/19 08:20:23 tholo Exp $
+#	$OpenBSD: Makefile.inc,v 1.3 1998/11/20 11:18:34 d Exp $
 
-.PATH: ${.CURDIR}/db/db
+.PATH: ${LIBCSRCDIR}/db/db
 
 SRCS+=	db.c
diff --git a/lib/libc/db/hash/Makefile.inc b/lib/libc/db/hash/Makefile.inc
index a25fd9d0c9b..8022fe41e68 100644
--- a/lib/libc/db/hash/Makefile.inc
+++ b/lib/libc/db/hash/Makefile.inc
@@ -1,6 +1,6 @@
-#	$OpenBSD: Makefile.inc,v 1.3 1996/08/19 08:20:27 tholo Exp $
+#	$OpenBSD: Makefile.inc,v 1.4 1998/11/20 11:18:35 d Exp $
 
-.PATH: ${.CURDIR}/db/hash
+.PATH: ${LIBCSRCDIR}/db/hash
 
 SRCS+=	hash.c hash_bigkey.c hash_buf.c hash_func.c hash_log2.c \
 	hash_page.c hsearch.c ndbm.c
diff --git a/lib/libc/db/man/Makefile.inc b/lib/libc/db/man/Makefile.inc
index beea08edc40..8683e93b17b 100644
--- a/lib/libc/db/man/Makefile.inc
+++ b/lib/libc/db/man/Makefile.inc
@@ -1,6 +1,6 @@
-#	$OpenBSD: Makefile.inc,v 1.6 1998/07/23 07:18:01 deraadt Exp $
+#	$OpenBSD: Makefile.inc,v 1.7 1998/11/20 11:18:35 d Exp $
 
-.PATH: ${.CURDIR}/db/man
+.PATH: ${LIBCSRCDIR}/db/man
 
 MAN+=	btree.3 dbopen.3 hash.3 recno.3 ndbm.3 mpool.3
 MLINKS+= dbopen.3 db.3
diff --git a/lib/libc/db/mpool/Makefile.inc b/lib/libc/db/mpool/Makefile.inc
index 34cc816eef7..2e8eaf54761 100644
--- a/lib/libc/db/mpool/Makefile.inc
+++ b/lib/libc/db/mpool/Makefile.inc
@@ -1,5 +1,5 @@
-#	$OpenBSD: Makefile.inc,v 1.2 1996/08/19 08:20:49 tholo Exp $
+#	$OpenBSD: Makefile.inc,v 1.3 1998/11/20 11:18:36 d Exp $
 
-.PATH: ${.CURDIR}/db/mpool
+.PATH: ${LIBCSRCDIR}/db/mpool
 
 SRCS+=	mpool.c
diff --git a/lib/libc/db/recno/Makefile.inc b/lib/libc/db/recno/Makefile.inc
index a6fa64b5653..e9976e019d5 100644
--- a/lib/libc/db/recno/Makefile.inc
+++ b/lib/libc/db/recno/Makefile.inc
@@ -1,6 +1,6 @@
-#	$OpenBSD: Makefile.inc,v 1.3 1996/08/19 08:20:54 tholo Exp $
+#	$OpenBSD: Makefile.inc,v 1.4 1998/11/20 11:18:36 d Exp $
 
-.PATH: ${.CURDIR}/db/recno
+.PATH: ${LIBCSRCDIR}/db/recno
 
 SRCS+=	rec_close.c rec_delete.c rec_get.c rec_open.c rec_put.c rec_search.c \
 	rec_seq.c rec_utils.c
diff --git a/lib/libc/gen/Makefile.inc b/lib/libc/gen/Makefile.inc
index da3a40534c5..3ca692f95a8 100644
--- a/lib/libc/gen/Makefile.inc
+++ b/lib/libc/gen/Makefile.inc
@@ -1,7 +1,7 @@
-#	$OpenBSD: Makefile.inc,v 1.18 1998/08/29 21:11:21 deraadt Exp $
+#	$OpenBSD: Makefile.inc,v 1.19 1998/11/20 11:18:37 d Exp $
 
 # gen sources
-.PATH: ${.CURDIR}/arch/${MACHINE_ARCH}/gen ${.CURDIR}/gen
+.PATH: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/gen ${LIBCSRCDIR}/gen
 
 SRCS+=	alarm.c assert.c basename.c clock.c closedir.c confstr.c ctermid.c \
 	ctype_.c daemon.c devname.c dirname.c disklabel.c elf_hash.c err.c \
@@ -28,14 +28,14 @@ SRCS+=	_err.c _errx.c _sys_errlist.c _sys_nerr.c _sys_siglist.c \
 #	_setjmp() fabs() frexp() infinity isinf() ldexp() modf()
 #	setjmp() sigsetjmp()
 
-.include "${.CURDIR}/arch/${MACHINE_ARCH}/gen/Makefile.inc"
+.include "${LIBCSRCDIR}/arch/${MACHINE_ARCH}/gen/Makefile.inc"
 
 .ifdef _NOTDEF_XXX_
 
 .if (${MACHINE} == "tahoe" )
 errlst.o errlst.po:
 	${CC} -S ${CFLAGS} ${.IMPSRC}
-	ed - < ${.CURDIR}/${MACHINE}/:errfix errlst.s
+	ed - < ${LIBCSRCDIR}/${MACHINE}/:errfix errlst.s
 	${AS} -o ${.TARGET} errlst.s
 	rm -f errlst.s
 .endif
diff --git a/lib/libc/arch/i386/sys/setlogin.S b/lib/libc/gen/_spinlock_stub.c
index acd1144725d..5d95a8aadd5 100644
--- a/lib/libc/arch/i386/sys/setlogin.S
+++ b/lib/libc/gen/_spinlock_stub.c
@@ -1,10 +1,7 @@
-/*-
- * Copyright (c) 1991 The Regents of the University of California.
+/*
+ * Copyright (c) 1998 John Birrell <jb@cimlogic.com.au>.
  * All rights reserved.
  *
- * This code is derived from software contributed to Berkeley by
- * William Jolitz.
- *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
@@ -15,13 +12,12 @@
  *    documentation and/or other materials provided with the distribution.
  * 3. All advertising materials mentioning features or use of this software
  *    must display the following acknowledgement:
- *	This product includes software developed by the University of
- *	California, Berkeley and its contributors.
- * 4. Neither the name of the University nor the names of its contributors
+ *	This product includes software developed by John Birrell.
+ * 4. Neither the name of the author nor the names of any co-contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
@@ -32,24 +28,26 @@
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
+ *
+ * $Id: _spinlock_stub.c,v 1.1 1998/11/20 11:18:37 d Exp $
+ * $OpenBSD: _spinlock_stub.c,v 1.1 1998/11/20 11:18:37 d Exp $
+ *
  */
 
-#include "SYS.h"
+#include <stdio.h>
+#include <thread_private.h>
+
+/* Don't build these stubs into libc_r: */
+#ifndef	_THREAD_SAFE
+#include "spinlock.h"
 
-#if defined(SYSLIBC_SCCS)
-	.text
-	.asciz "$OpenBSD: setlogin.S,v 1.2 1996/08/19 08:13:39 tholo Exp $"
-#endif /* SYSLIB_SCCS */
+void
+_spinlock(spinlock_t *lck)
+{
+}
 
-	.globl	___logname_valid	/* in getlogin() */
-SYSCALL(setlogin)
-	xorl	%eax,%eax
-#ifdef PIC
-	PIC_PROLOGUE
-	movl	PIC_GOT(___logname_valid),%edx
-	PIC_EPILOGUE
-	movl	%eax,(%edx)
-#else
-	movl	%eax,___logname_valid
+void
+_spinlock_debug(spinlock_t *lck, char *fname, int lineno)
+{
+}
 #endif
-	ret				/* setlogin(name) */
diff --git a/lib/libc/gen/closedir.c b/lib/libc/gen/closedir.c
index 21a8375a8a5..11193a12e8a 100644
--- a/lib/libc/gen/closedir.c
+++ b/lib/libc/gen/closedir.c
@@ -32,13 +32,14 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: closedir.c,v 1.2 1996/08/19 08:21:55 tholo Exp $";
+static char rcsid[] = "$OpenBSD: closedir.c,v 1.3 1998/11/20 11:18:37 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <sys/types.h>
 #include <dirent.h>
 #include <stdlib.h>
 #include <unistd.h>
+#include "thread_private.h"
 
 /*
  * close a directory.
@@ -48,12 +49,17 @@ closedir(dirp)
 	register DIR *dirp;
 {
 	int fd;
+	int ret;
 
+	if ((ret = _FD_LOCK(dirp->dd_fd, FD_READ, NULL)) != 0)
+		return (ret);
 	seekdir(dirp, dirp->dd_rewind);	/* free seekdir storage */
 	fd = dirp->dd_fd;
 	dirp->dd_fd = -1;
 	dirp->dd_loc = 0;
 	free((void *)dirp->dd_buf);
 	free((void *)dirp);
-	return(close(fd));
+	ret = close(fd);
+	_FD_UNLOCK(fd, FD_READ);
+	return (ret);
 }
diff --git a/lib/libc/gen/ctermid.c b/lib/libc/gen/ctermid.c
index 9bb0a594880..8b4d46d1f1c 100644
--- a/lib/libc/gen/ctermid.c
+++ b/lib/libc/gen/ctermid.c
@@ -32,7 +32,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: ctermid.c,v 1.2 1996/08/19 08:22:03 tholo Exp $";
+static char rcsid[] = "$OpenBSD: ctermid.c,v 1.3 1998/11/20 11:18:37 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <stdio.h>
@@ -51,3 +51,13 @@ ctermid(s)
 	}
 	return(def);
 }
+
+char *
+ctermid_r(s)
+	char *s;
+{
+	if (s)
+		return ctermid(s);
+	else
+		return(NULL);
+}
diff --git a/lib/libc/gen/getgrent.c b/lib/libc/gen/getgrent.c
index df1f2a6d433..3660df72953 100644
--- a/lib/libc/gen/getgrent.c
+++ b/lib/libc/gen/getgrent.c
@@ -33,7 +33,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: getgrent.c,v 1.8 1997/12/19 09:42:22 deraadt Exp $";
+static char rcsid[] = "$OpenBSD: getgrent.c,v 1.9 1998/11/20 11:18:37 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <sys/types.h>
@@ -48,12 +48,16 @@ static char rcsid[] = "$OpenBSD: getgrent.c,v 1.8 1997/12/19 09:42:22 deraadt Ex
 #include <rpcsvc/ypclnt.h>
 #include "ypinternal.h"
 #endif
+#include "thread_private.h"
 
+_THREAD_PRIVATE_KEY(gr)
+_THREAD_PRIVATE_MUTEX(gr)
 static FILE *_gr_fp;
 static struct group _gr_group;
 static int _gr_stayopen;
-static int grscan __P((int, gid_t, const char *));
+static int grscan __P((int, gid_t, const char *, struct group *));
 static int start_gr __P((void));
+static void endgrent_basic __P((void));
 
 #define	MAXGRP		200
 static char *members[MAXGRP];
@@ -68,43 +72,78 @@ static int	__ypcurrentlen;
 #endif
 
 struct group *
+getgrent_r(p_gr)
+struct group * p_gr;
+{
+	_THREAD_PRIVATE_MUTEX_LOCK(gr);
+	if ((!_gr_fp && !start_gr()) || !grscan(0, 0, NULL, p_gr))
+		p_gr = NULL;
+	_THREAD_PRIVATE_MUTEX_UNLOCK(gr);
+	return (p_gr);
+}
+
+struct group *
 getgrent()
 {
-	if ((!_gr_fp && !start_gr()) || !grscan(0, 0, NULL))
-		return(NULL);
-	return(&_gr_group);
+	struct group *p_gr = (struct group*)_THREAD_PRIVATE(gr,_gr_group,NULL);
+
+	return getgrent_r(p_gr);
 }
 
 struct group *
-getgrnam(name)
+getgrnam_r(name, p_gr)
 	const char *name;
+	struct group *p_gr;
 {
 	int rval;
 
+	_THREAD_PRIVATE_MUTEX_LOCK(gr);
 	if (!start_gr())
-		return(NULL);
-	rval = grscan(1, 0, name);
-	if (!_gr_stayopen)
-		endgrent();
-	return(rval ? &_gr_group : NULL);
+		rval = 0;
+	else {
+		rval = grscan(1, 0, name, p_gr);
+		if (!_gr_stayopen)
+			endgrent_basic();
+	}
+	_THREAD_PRIVATE_MUTEX_UNLOCK(gr);
+	return(rval ? p_gr : NULL);
 }
 
 struct group *
-#ifdef __STDC__
-getgrgid(gid_t gid)
-#else
-getgrgid(gid)
+getgrnam(name)
+	const char *name;
+{
+	struct group *p_gr = (struct group*)_THREAD_PRIVATE(gr,_gr_group,NULL);
+
+	return getgrnam_r(name, p_gr);
+}
+
+struct group *
+getgrgid_r(gid, p_gr)
 	gid_t gid;
-#endif
+	struct group * p_gr;
 {
 	int rval;
 
+	_THREAD_PRIVATE_MUTEX_LOCK(gr);
 	if (!start_gr())
-		return(NULL);
-	rval = grscan(1, gid, NULL);
-	if (!_gr_stayopen)
-		endgrent();
-	return(rval ? &_gr_group : NULL);
+		rval = 0;
+	else {
+		rval = grscan(1, gid, NULL, p_gr);
+		if (!_gr_stayopen)
+			endgrent_basic();
+	}
+	_THREAD_PRIVATE_MUTEX_UNLOCK(gr);
+	return(rval ? p_gr : NULL);
+}
+
+struct group *
+getgrgid(gid)
+	gid_t gid;
+{
+	struct group *p_gr = (struct group*)_THREAD_PRIVATE(gr,_gr_group,NULL);
+
+	return getgrgid_r(gid, p_gr);
 }
 
 static int
@@ -133,14 +172,22 @@ int
 setgroupent(stayopen)
 	int stayopen;
 {
+	int retval;
+
+	_THREAD_PRIVATE_MUTEX_LOCK(gr);
 	if (!start_gr())
-		return(0);
-	_gr_stayopen = stayopen;
-	return(1);
+		retval = 0;
+	else {
+		_gr_stayopen = stayopen;
+		retval = 1;
+	}
+	_THREAD_PRIVATE_MUTEX_LOCK(gr);
+	return (retval);
 }
 
+static
 void
-endgrent()
+endgrent_basic()
 {
 	if (_gr_fp) {
 		(void)fclose(_gr_fp);
@@ -154,11 +201,20 @@ endgrent()
 	}
 }
 
+void
+endgrent()
+{
+	_THREAD_PRIVATE_MUTEX_LOCK(gr);
+	endgrent_basic();
+	_THREAD_PRIVATE_MUTEX_UNLOCK(gr);
+}
+
 static int
-grscan(search, gid, name)
+grscan(search, gid, name, p_gr)
 	register int search;
 	register gid_t gid;
 	register const char *name;
+	struct group * p_gr;
 {
 	register char *cp, **m;
 	char *bp;
@@ -282,12 +338,12 @@ grscan(search, gid, name)
 					free(data);
 					line[datalen] = '\0';
 					bp = line;
-					_gr_group.gr_name = strsep(&bp, ":\n");
-					_gr_group.gr_passwd =
+					p_gr->gr_name = strsep(&bp, ":\n");
+					p_gr->gr_passwd =
 						strsep(&bp, ":\n");
 					if (!(cp = strsep(&bp, ":\n")))
 						continue;
-					_gr_group.gr_gid =
+					p_gr->gr_gid =
 						name ? atoi(cp) : gid;
 					goto found_it;
 				}
@@ -308,20 +364,20 @@ grscan(search, gid, name)
 		}
 parse:
 #endif
-		_gr_group.gr_name = strsep(&bp, ":\n");
-		if (search && name && strcmp(_gr_group.gr_name, name))
+		p_gr->gr_name = strsep(&bp, ":\n");
+		if (search && name && strcmp(p_gr->gr_name, name))
 			continue;
-		_gr_group.gr_passwd = strsep(&bp, ":\n");
+		p_gr->gr_passwd = strsep(&bp, ":\n");
 		if (!(cp = strsep(&bp, ":\n")))
 			continue;
-		_gr_group.gr_gid = atoi(cp);
-		if (search && name == NULL && _gr_group.gr_gid != gid)
+		p_gr->gr_gid = atoi(cp);
+		if (search && name == NULL && p_gr->gr_gid != gid)
 			continue;
 	found_it:
 		cp = NULL;
 		if (bp == NULL)
 			continue;
-		for (m = _gr_group.gr_mem = members;; bp++) {
+		for (m = p_gr->gr_mem = members;; bp++) {
 			if (m == &members[MAXGRP - 1])
 				break;
 			if (*bp == ',') {
diff --git a/lib/libc/gen/getlogin.c b/lib/libc/gen/getlogin.c
index abf13131da3..b532c406246 100644
--- a/lib/libc/gen/getlogin.c
+++ b/lib/libc/gen/getlogin.c
@@ -32,7 +32,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: getlogin.c,v 1.3 1997/07/09 00:28:21 millert Exp $";
+static char rcsid[] = "$OpenBSD: getlogin.c,v 1.4 1998/11/20 11:18:39 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <sys/param.h>
@@ -41,19 +41,68 @@ static char rcsid[] = "$OpenBSD: getlogin.c,v 1.3 1997/07/09 00:28:21 millert Ex
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
+#include <errno.h>
+#include "thread_private.h"
+
+_THREAD_PRIVATE_MUTEX(logname)
+static int  logname_valid = 0;
+static char logname[MAXLOGNAME + 1];
 
-int	__logname_valid;		/* known to setlogin() */
 int	_getlogin __P((char *, size_t));
+int	_setlogin __P((const char *));
 
 char *
 getlogin()
 {
-	static char logname[MAXLOGNAME + 1];
+	_THREAD_PRIVATE_KEY(getlogin)
+	char * name = (char *)_THREAD_PRIVATE(getlogin, logname, NULL);
 
-	if (__logname_valid == 0) {
-		if (_getlogin(logname, sizeof(logname) - 1) < 0)
-			return ((char *)NULL);
-		__logname_valid = 1;
+	if ((errno = getlogin_r(name, sizeof logname)) != 0)
+		return NULL;
+	if (*name == '\0') {
+		errno = ENOENT;  /* well? */
+		return NULL;
 	}
-	return (*logname ? logname : (char *)NULL);
+	return name;
+}
+
+int
+getlogin_r(name, namelen)
+	char *name;
+	size_t namelen;
+{
+	int logname_size;
+
+	if (name == NULL)
+		return EFAULT;
+
+	_THREAD_PRIVATE_MUTEX_LOCK(logname);
+	if (!logname_valid) {
+		if (_getlogin(logname, sizeof(logname) - 1) < 0) {
+			_THREAD_PRIVATE_MUTEX_UNLOCK(logname);
+			return errno;
+		}
+		logname_valid = 1;
+		logname[MAXLOGNAME] = '\0';	/* paranoia */
+	}
+	logname_size = strlen(logname) + 1;
+	if (namelen < logname_size)
+		return ERANGE;
+	memcpy(name, logname, logname_size);
+	_THREAD_PRIVATE_MUTEX_UNLOCK(logname);
+	return 0;
+}
+
+int
+setlogin(name)
+	const char *name;
+{
+	int ret;
+
+	_THREAD_PRIVATE_MUTEX_LOCK(logname);
+	ret = _setlogin(name);
+	if (ret == 0)
+		logname_valid = 0;
+	_THREAD_PRIVATE_MUTEX_UNLOCK(logname);
+	return ret;
 }
diff --git a/lib/libc/gen/isatty.c b/lib/libc/gen/isatty.c
index d4dc9ad6cf6..f32cf3eaeb5 100644
--- a/lib/libc/gen/isatty.c
+++ b/lib/libc/gen/isatty.c
@@ -32,17 +32,25 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: isatty.c,v 1.2 1996/08/19 08:24:32 tholo Exp $";
+static char rcsid[] = "$OpenBSD: isatty.c,v 1.3 1998/11/20 11:18:39 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <termios.h>
 #include <unistd.h>
+#include "thread_private.h"
 
 int
 isatty(fd)
 	int fd;
 {
+	int retval;
 	struct termios t;
 
-	return(tcgetattr(fd, &t) != -1);
+	if (_FD_LOCK(fd, FD_READ, NULL) == 0) {
+		retval = (tcgetattr(fd, &t) != -1);
+		_FD_UNLOCK(fd, FD_READ);
+	} else {
+		retval = 0;
+	}
+	return(retval);
 }
diff --git a/lib/libc/gen/readdir.c b/lib/libc/gen/readdir.c
index d73ebcd2843..3d3b2a2012b 100644
--- a/lib/libc/gen/readdir.c
+++ b/lib/libc/gen/readdir.c
@@ -32,11 +32,13 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: readdir.c,v 1.2 1996/08/19 08:25:35 tholo Exp $";
+static char rcsid[] = "$OpenBSD: readdir.c,v 1.3 1998/11/20 11:18:39 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <sys/param.h>
 #include <dirent.h>
+#include <errno.h>
+#include "thread_private.h"
 
 /*
  * get next entry in a directory.
@@ -73,3 +75,33 @@ readdir(dirp)
 		return (dp);
 	}
 }
+
+int
+readdir_r(dirp, entry, result)
+	DIR *dirp;
+	struct dirent *entry;
+	struct dirent **result;
+{
+	struct dirent *dp;
+	int ret;
+
+	if (dirp->dd_fd < 0) {
+		return EBADF;
+	}
+	if ((ret = _FD_LOCK(dirp->dd_fd, FD_READ, NULL)) != 0)
+		return ret;
+	errno = 0;
+	dp = readdir(dirp);
+	if (dp == NULL && errno != 0) {
+		_FD_UNLOCK(dirp->dd_fd, FD_READ);
+		return errno;
+	}
+	if (dp != NULL) 
+		memcpy(entry, dp, sizeof *entry);
+	_FD_UNLOCK(dirp->dd_fd, FD_READ);
+	if (dp != NULL)
+	*result = entry;
+	else
+		*result = NULL;
+	return 0;
+}
diff --git a/lib/libc/gen/ttyname.3 b/lib/libc/gen/ttyname.3
index 76830b638d2..728bc1509e3 100644
--- a/lib/libc/gen/ttyname.3
+++ b/lib/libc/gen/ttyname.3
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: ttyname.3,v 1.4 1998/06/08 17:21:45 deraadt Exp $
+.\"	$OpenBSD: ttyname.3,v 1.5 1998/11/20 11:18:40 d Exp $
 .\"
 .\" Copyright (c) 1991, 1993
 .\"	The Regents of the University of California.  All rights reserved.
@@ -36,6 +36,7 @@
 .Os
 .Sh NAME
 .Nm ttyname ,
+.Nm ttyname_r ,
 .Nm isatty ,
 .Nm ttyslot
 .Nd get name of associated terminal (tty) from file descriptor
@@ -44,6 +45,8 @@
 .Ft char *
 .Fn ttyname "int fd"
 .Ft int
+.Fn ttyname_r "int fd" "char *name" "size_t namesize"
+.Ft int
 .Fn isatty "int fd"
 .Ft int
 .Fn ttyslot "void"
@@ -72,11 +75,25 @@ terminal type device.
 .Pp
 The
 .Fn ttyname
-function
-gets the related device name of
+and
+.Fn ttyname_r
+functions
+get the related device name of
 a file descriptor for which
 .Fn isatty
-is true
+is true.
+The
+.Fn ttyname_r
+function stores the nul-terminated pathname of the terminal associated with 
+the file descriptor
+.Fa fd
+in the character array referenced by
+.Fa name .
+The array is
+.Fa namesize
+characters long and should have space for the name and the terminating nul
+character. The maximum length of the terminal name is
+.Dv TTY_NAME_MAX .
 .Pp
 The
 .Fn ttyslot
@@ -87,8 +104,10 @@ file entry.
 .Sh RETURN VALUES
 The
 .Fn ttyname
-function
-returns the null terminated name if the device is found and
+and
+.Fn ttyname_r
+functions
+return the nul terminated name if the device is found and
 .Fn isatty
 is true; otherwise 
 a
@@ -125,6 +144,11 @@ argument is not a valid file descriptor.
 The
 .Fa fd
 argument does not refer to a terminal device.
+.It Bq Er ERANGE
+The value of 
+.Fa namesize
+is smaller than the length of the string to be returned including the
+terminating nul character.
 .El
 .Sh FILES
 .Bl -tag -width /etc/ttys -compact
@@ -133,7 +157,8 @@ argument does not refer to a terminal device.
 .El
 .Sh SEE ALSO
 .Xr ioctl 2 ,
-.Xr ttys 5
+.Xr ttys 5 ,
+.Xr dev_mkdb 8
 .Sh HISTORY
 A
 .Fn isatty ,
@@ -143,6 +168,9 @@ and
 function
 appeared in
 .At v7 .
+The
+.Fn ttyname_r
+function appeared in the POSIX Threads Extension (1003.1c-1995).
 .Sh BUGS
 The
 .Fn ttyname
diff --git a/lib/libc/gen/ttyname.c b/lib/libc/gen/ttyname.c
index 192072a208f..a18b68fdd2c 100644
--- a/lib/libc/gen/ttyname.c
+++ b/lib/libc/gen/ttyname.c
@@ -32,7 +32,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: ttyname.c,v 1.5 1998/08/27 06:42:16 deraadt Exp $";
+static char rcsid[] = "$OpenBSD: ttyname.c,v 1.6 1998/11/20 11:18:40 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <sys/types.h>
@@ -44,13 +44,49 @@ static char rcsid[] = "$OpenBSD: ttyname.c,v 1.5 1998/08/27 06:42:16 deraadt Exp
 #include <string.h>
 #include <unistd.h>
 #include <paths.h>
+#include <limits.h>
+#include <errno.h>
+#include "thread_private.h"
 
-static char buf[sizeof(_PATH_DEV) + MAXNAMLEN];
-static char *oldttyname __P((int, struct stat *));
+static char buf[TTY_NAME_MAX];
+static int oldttyname __P((int, struct stat *, char *, size_t));
+static int __ttyname_r_basic __P((int, char *, size_t));
+
+int
+ttyname_r(int fd, char *buf, size_t buflen)
+{
+	int ret;
+
+	if ((ret = _FD_LOCK(fd, FD_READ, NULL)) == 0) {
+		ret = __ttyname_r_basic(fd, buf, buflen);
+		_FD_UNLOCK(fd, FD_READ);
+	}
+	return ret;
+}
 
 char *
-ttyname(fd)
+ttyname(int fd)
+{
+	_THREAD_PRIVATE_KEY(ttyname)
+	char * bufp = (char*) _THREAD_PRIVATE(ttyname, buf, NULL);
+	int err;
+
+	if (bufp == NULL) 
+		return NULL;
+	err = ttyname_r(fd, bufp, sizeof buf);
+	if (err) {
+		errno = err;
+		return NULL;
+	}
+	else
+	return bufp;
+}
+
+static int
+__ttyname_r_basic(fd, buf, len)
 	int fd;
+	char *buf;
+	size_t len;
 {
 	struct stat sb;
 	struct termios ttyb;
@@ -63,10 +99,14 @@ ttyname(fd)
 
 	/* Must be a terminal. */
 	if (tcgetattr(fd, &ttyb) < 0)
-		return (NULL);
+		return (errno);
 	/* Must be a character device. */
-	if (fstat(fd, &sb) || !S_ISCHR(sb.st_mode))
-		return (NULL);
+	if (fstat(fd, &sb))
+		return (errno);
+	if (!S_ISCHR(sb.st_mode))
+		return (ENOTTY);
+	if (len < sizeof(_PATH_DEV))
+		return (ERANGE);
 
 	memcpy(buf, _PATH_DEV, sizeof(_PATH_DEV));
 
@@ -77,40 +117,50 @@ ttyname(fd)
 		key.data = &bkey;
 		key.size = sizeof(bkey);
 		if (!(db->get)(db, &key, &data, 0)) {
+			if (data.size > len - (sizeof(_PATH_DEV) - 1)) {
+				(void)(db->close)(db);
+				return (ERANGE);
+			}
 			memcpy(buf + sizeof(_PATH_DEV) - 1, data.data,
 			    data.size);
 			(void)(db->close)(db);
-			return (buf);
+			return (0);
 		}
 		(void)(db->close)(db);
 	}
-	return (oldttyname(fd, &sb));
+	return (oldttyname(fd, &sb, buf, len));
 }
 
 /* ARGSUSED */
-static char *
-oldttyname(fd, sb)
+static int
+oldttyname(fd, sb, buf, len)
 	int fd;
 	struct stat *sb;
+	char *buf;
+	size_t len;
 {
 	register struct dirent *dirp;
 	register DIR *dp;
 	struct stat dsb;
 
 	if ((dp = opendir(_PATH_DEV)) == NULL)
-		return (NULL);
+		return (errno);
 
 	while ((dirp = readdir(dp))) {
 		if (dirp->d_fileno != sb->st_ino)
 			continue;
+		if (dirp->d_namlen > len - sizeof(_PATH_DEV)) {
+			(void)closedir(dp);
+			return (ERANGE);
+		}
 		memcpy(buf + sizeof(_PATH_DEV) - 1, dirp->d_name,
 		    dirp->d_namlen + 1);
 		if (stat(buf, &dsb) || sb->st_dev != dsb.st_dev ||
 		    sb->st_ino != dsb.st_ino)
 			continue;
 		(void)closedir(dp);
-		return (buf);
+		return (0);
 	}
 	(void)closedir(dp);
-	return (NULL);
+	return (ENOTTY);
 }
diff --git a/lib/libc/gmon/Makefile.inc b/lib/libc/gmon/Makefile.inc
index 3c4d53b572f..f7c3e1ff6db 100644
--- a/lib/libc/gmon/Makefile.inc
+++ b/lib/libc/gmon/Makefile.inc
@@ -1,7 +1,7 @@
-#	$OpenBSD: Makefile.inc,v 1.3 1998/08/29 21:11:38 deraadt Exp $
+#	$OpenBSD: Makefile.inc,v 1.4 1998/11/20 11:18:40 d Exp $
 
 # gmon sources
-.PATH: ${.CURDIR}/gmon
+.PATH: ${LIBCSRCDIR}/gmon
 
 SRCS+=	gmon.c mcount.c
 MAN+=	moncontrol.3
diff --git a/lib/libc/hash/Makefile.inc b/lib/libc/hash/Makefile.inc
index d198805fbbf..e40edc01b8d 100644
--- a/lib/libc/hash/Makefile.inc
+++ b/lib/libc/hash/Makefile.inc
@@ -1,7 +1,7 @@
-#	$OpenBSD: Makefile.inc,v 1.5 1997/07/17 06:02:42 millert Exp $
+#	$OpenBSD: Makefile.inc,v 1.6 1998/11/20 11:18:41 d Exp $
 
 # hash functions
-.PATH: ${.CURDIR}/hash
+.PATH: ${LIBCSRCDIR}/hash
 
 SRCS+=	sha1.c sha1hl.c rmd160.c rmd160hl.c
 MAN+=	sha1.3 rmd160.3
diff --git a/lib/libc/include/spinlock.h b/lib/libc/include/spinlock.h
new file mode 100644
index 00000000000..e4871f9aede
--- /dev/null
+++ b/lib/libc/include/spinlock.h
@@ -0,0 +1,73 @@
+/*
+ * Copyright (c) 1998 John Birrell <jb@cimlogic.com.au>.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by John Birrell.
+ * 4. Neither the name of the author nor the names of any co-contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $Id: spinlock.h,v 1.1 1998/11/20 11:18:41 d Exp $
+ * $OpenBSD: spinlock.h,v 1.1 1998/11/20 11:18:41 d Exp $
+ *
+ * Lock definitions used in both libc and libpthread.
+ *
+ */
+
+#ifndef _SPINLOCK_H_
+#define _SPINLOCK_H_
+#include <sys/cdefs.h>
+#include <sys/types.h>
+
+/*
+ * Lock structure with room for debugging information.
+ */
+typedef struct {
+	volatile register_t	access_lock;
+	volatile long	lock_owner;
+	volatile const char * fname;
+	volatile int	lineno;
+} spinlock_t;
+
+#define	_SPINLOCK_INITIALIZER	{ 0, 0, 0, 0 }
+
+#define _SPINUNLOCK(_lck)	(_lck)->access_lock = 0
+#ifdef	_LOCK_DEBUG
+#define	_SPINLOCK(_lck)		_spinlock_debug(_lck, __FILE__, __LINE__)
+#else
+#define	_SPINLOCK(_lck)		_spinlock(_lck)
+#endif
+
+/*
+ * Thread function prototype definitions:
+ */
+__BEGIN_DECLS
+register_t	_atomic_lock __P((volatile register_t *));
+register_t	_thread_slow_atomic_lock __P((volatile register_t *));
+void	_spinlock __P((spinlock_t *));
+void	_spinlock_debug __P((spinlock_t *, const char *, int));
+__END_DECLS
+
+#endif /* _SPINLOCK_H_ */
diff --git a/lib/libc/include/thread_private.h b/lib/libc/include/thread_private.h
new file mode 100644
index 00000000000..a7f77490780
--- /dev/null
+++ b/lib/libc/include/thread_private.h
@@ -0,0 +1,175 @@
+/*
+ *
+ * Support for thread-safety in libc and libc_r common code using macros 
+ * to declare thread-safe data structures.
+ *
+ * $OpenBSD: thread_private.h,v 1.1 1998/11/20 11:18:41 d Exp $
+ */
+
+#ifndef _THREAD_PRIVATE_H_
+#define _THREAD_PRIVATE_H_
+
+/*
+ * Parts of this file are
+ * Copyright (c) 1998 John Birrell <jb@cimlogic.com.au>.
+ * All rights reserved.
+ *
+ * $Id: thread_private.h,v 1.1 1998/11/20 11:18:41 d Exp $
+ * $OpenBSD: thread_private.h,v 1.1 1998/11/20 11:18:41 d Exp $
+ */
+
+/*
+ * This global flag is non-zero when a process has created one
+ * or more threads. It is used to avoid calling locking functions
+ * when they are not required. In libc, this is always assumed
+ * to be zero.
+ */
+
+extern volatile int	__isthreaded;
+
+#ifdef _THREAD_SAFE
+
+#include <pthread.h>
+#include "pthread_private.h"
+
+#ifdef __STDC__
+#define __THREAD_MUTEXP_NAME(name)	_thread_mutexp_inst__ ## name
+#define __THREAD_MUTEX_NAME(name)	_thread_mutex_inst__ ## name
+#define __THREAD_KEY_NAME(name)		_thread_key_inst__ ## name
+#else
+#define __THREAD_MUTEXP_NAME(name)	_thread_mutexp_inst__/**/name
+#define __THREAD_MUTEX_NAME(name)	_thread_mutex_inst__/**/name
+#define __THREAD_KEY_NAME(name)		_thread_key_inst__/**/name
+#endif
+
+/*
+ * Mutex declare, lock and unlock macros.
+ */
+
+#define _THREAD_PRIVATE_MUTEX(name)					\
+	static struct pthread_mutex __THREAD_MUTEXP_NAME(name) =	\
+		PTHREAD_MUTEX_STATIC_INITIALIZER;			\
+	static pthread_mutex_t __THREAD_MUTEX_NAME(name) = 		\
+		&__THREAD_MUTEXP_NAME(name);
+		
+#define _THREAD_PRIVATE_MUTEX_LOCK(name) 				\
+	pthread_mutex_lock(&__THREAD_MUTEX_NAME(name))
+		
+#define _THREAD_PRIVATE_MUTEX_UNLOCK(name) 				\
+	pthread_mutex_unlock(&__THREAD_MUTEX_NAME(name))
+
+/*
+ * These macros help in making persistent storage thread-specific.
+ * Libc makes extensive use of private static data structures
+ * that hold state across function invocation, and these macros
+ * are no-ops when _THREAD_SAFE is not defined. 
+ * In a thread-safe library, the static variables are used only for
+ * initialising the per-thread instances of the state variables.
+ */
+
+/*
+ * a mutexed data structure used to hold the persistent state's key
+ */
+struct _thread_private_key_struct {
+	struct pthread_mutex	lockd;
+	pthread_mutex_t		lock;
+	int			init;
+	pthread_key_t		key;
+};
+
+/*
+ * Declaration of a per-thread state key.
+ */
+#define _THREAD_PRIVATE_KEY(name)					\
+	static volatile struct _thread_private_key_struct		\
+	__THREAD_KEY_NAME(name) = {					\
+		PTHREAD_MUTEX_STATIC_INITIALIZER, 			\
+		&__THREAD_KEY_NAME(name).lockd,				\
+		0							\
+	};
+
+/*
+ * Initialisation of storage space for a per-thread state variable.
+ * A pointer to a per-thread *copy* of the _initv parameter is returned.
+ * It calls malloc the first time and the space is automatically free'd
+ * when the thread dies. If you need something a bit more complicated
+ * than free() you will need to roll-your-own.
+ */
+#define _THREAD_PRIVATE(keyname, _initv, _errv) 			\
+	({								\
+		struct _thread_private_key_struct * __k = 		\
+			&__THREAD_KEY_NAME(keyname);			\
+		void* __p;						\
+		extern void free __P((void*));				\
+		extern void* malloc __P((size_t));			\
+									\
+		if (!__isthreaded) {					\
+			/* non-threaded behaviour */			\
+			__p = &(_initv);				\
+			goto _ok;					\
+		}							\
+									\
+		/* create key for first thread */			\
+		pthread_mutex_lock(&__k->lock);				\
+		if (__k->init == 0) {					\
+			if (pthread_key_create(&__k->key, free)) {	\
+				pthread_mutex_unlock(&__k->lock);	\
+				goto _err;				\
+			}						\
+			__k->init = 1;					\
+		}							\
+		pthread_mutex_unlock(&__k->lock);			\
+									\
+		if ((__p = pthread_getspecific(__k->key)) == NULL) {	\
+			/* alloc space on 1st call in this thread */	\
+			if ((__p = malloc(sizeof(_initv))) == NULL) 	\
+				goto _err;				\
+				if (pthread_setspecific(__k->key, __p) != 0) { \
+					free(__p);			\
+					goto _err;			\
+				}					\
+			/* initialise with _initv */			\
+		memcpy(__p, &_initv, sizeof(_initv));			\
+		}							\
+		goto _ok;						\
+	_err:								\
+		__p = (_errv);						\
+	_ok:								\
+		__p;							\
+	})
+
+#else
+
+
+/*
+ * do-nothing macros for single-threaded case
+ */
+#define _FD_LOCK(f,o,p)				(0)
+#define _FD_UNLOCK(f,o)				/* nothing */
+#define _THREAD_PRIVATE_KEY(_key)		/* nothing */
+#define _THREAD_PRIVATE(keyname, _initv, _errv)	(&(_initv))
+#define _THREAD_PRIVATE_MUTEX(_name)		/* nothing */
+#define _THREAD_PRIVATE_MUTEX_LOCK(_name)	/* nothing */
+#define _THREAD_PRIVATE_MUTEX_UNLOCK(_name)	/* nothing */
+
+#endif
+
+/*
+ * File lock contention is difficult to diagnose without knowing
+ * where locks were set. Allow a debug library to be built which
+ * records the source file and line number of each lock call.
+ */
+#ifdef	_FLOCK_DEBUG
+#define _FLOCKFILE(x)	_flockfile_debug(x, __FILE__, __LINE__)
+#else
+#define _FLOCKFILE(x)	flockfile(x)
+#endif
+
+/*
+ * Macros for locking and unlocking FILEs. These test if the
+ * process is threaded to avoid locking when not required.
+ */
+#define	FLOCKFILE(fp)		if (__isthreaded) _FLOCKFILE(fp)
+#define	FUNLOCKFILE(fp)		if (__isthreaded) funlockfile(fp)
+
+#endif _THREAD_PRIVATE_H_
diff --git a/lib/libc/locale/Makefile.inc b/lib/libc/locale/Makefile.inc
index a01e92b975f..0784dda22f3 100644
--- a/lib/libc/locale/Makefile.inc
+++ b/lib/libc/locale/Makefile.inc
@@ -1,7 +1,7 @@
-#	$OpenBSD: Makefile.inc,v 1.3 1997/07/25 16:53:15 mickey Exp $
+#	$OpenBSD: Makefile.inc,v 1.4 1998/11/20 11:18:42 d Exp $
 
 # locale sources
-.PATH: ${.CURDIR}/arch/${MACHINE_ARCH}/locale ${.CURDIR}/locale
+.PATH: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/locale ${LIBCSRCDIR}/locale
 
 SRCS+=	_def_messages.c _def_monetary.c _def_numeric.c _def_time.c \
 	localeconv.c nl_langinfo.c setlocale.c
diff --git a/lib/libc/md/Makefile.inc b/lib/libc/md/Makefile.inc
index 17d2124e72f..c862c56e486 100644
--- a/lib/libc/md/Makefile.inc
+++ b/lib/libc/md/Makefile.inc
@@ -1,6 +1,6 @@
-#	$OpenBSD: Makefile.inc,v 1.4 1996/10/20 19:14:45 millert Exp $
+#	$OpenBSD: Makefile.inc,v 1.5 1998/11/20 11:18:42 d Exp $
 
-.PATH: ${.CURDIR}/md
+.PATH: ${LIBCSRCDIR}/md
 
 SRCS+=	md4c.c md5c.c md4hl.c md5hl.c
 
diff --git a/lib/libc/net/Makefile.inc b/lib/libc/net/Makefile.inc
index 935a1904c12..35a9632a94e 100644
--- a/lib/libc/net/Makefile.inc
+++ b/lib/libc/net/Makefile.inc
@@ -1,7 +1,7 @@
-#	$OpenBSD: Makefile.inc,v 1.16 1998/08/29 21:11:40 deraadt Exp $
+#	$OpenBSD: Makefile.inc,v 1.17 1998/11/20 11:18:43 d Exp $
 
 # net sources
-.PATH: ${.CURDIR}/arch/${MACHINE_ARCH}/net ${.CURDIR}/net
+.PATH: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/net ${LIBCSRCDIR}/net
 
 CFLAGS+=-DRESOLVSORT
 
@@ -19,7 +19,7 @@ SRCS+=	base64.c gethostnamadr.c getnetbyaddr.c getnetbyname.c getnetent.c \
 # m-d Makefile.inc must include sources for:
 #	htonl() htons() ntohl() ntohs()
 
-.include "${.CURDIR}/arch/${MACHINE_ARCH}/net/Makefile.inc"
+.include "${LIBCSRCDIR}/arch/${MACHINE_ARCH}/net/Makefile.inc"
 
 MAN+=	byteorder.3 ethers.3 gethostbyname.3 getnetent.3 getprotoent.3 \
 	getservent.3 inet.3 inet_net.3 iso_addr.3 link_addr.3 ns.3 ipx.3 \
diff --git a/lib/libc/net/gethostnamadr.c b/lib/libc/net/gethostnamadr.c
index 7321225863a..6ff456fb0c1 100644
--- a/lib/libc/net/gethostnamadr.c
+++ b/lib/libc/net/gethostnamadr.c
@@ -52,7 +52,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: gethostnamadr.c,v 1.30 1998/03/16 05:06:55 millert Exp $";
+static char rcsid[] = "$OpenBSD: gethostnamadr.c,v 1.31 1998/11/20 11:18:44 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <sys/param.h>
@@ -67,12 +67,14 @@ static char rcsid[] = "$OpenBSD: gethostnamadr.c,v 1.30 1998/03/16 05:06:55 mill
 #include <errno.h>
 #include <string.h>
 #include <syslog.h>
+#include <stdlib.h>
 #ifdef YP
 #include <rpc/rpc.h>
 #include <rpcsvc/yp.h>
 #include <rpcsvc/ypclnt.h>
 #include "ypinternal.h"
 #endif
+#include "thread_private.h"
 
 #define MULTI_PTRS_ARE_ALIASES 1	/* XXX - experimental */
 
@@ -423,6 +425,60 @@ getanswer(answer, anslen, qname, qtype)
 	return (NULL);
 }
 
+#ifndef notyet
+/*
+ * XXX This is an extremely bogus implementations.
+ *
+ * FreeBSD has this interface:
+ *    int gethostbyaddr_r(const char *addr, int len, int type,
+ *             struct hostent *result, struct hostent_data *buffer)
+ */
+
+struct hostent *
+gethostbyname_r(name, hp, buf, buflen, errorp)
+	const char * name;
+	struct hostent * hp;
+	char * buf;
+	int buflen;
+	int * errorp;
+{
+	struct hostent *res;
+
+	res = gethostbyname(name);
+	*errorp = h_errno;
+	if (res == NULL)
+		return NULL;
+	memcpy(hp, res, sizeof *hp); /* XXX not sufficient */
+	return hp;
+}
+
+/*
+ * XXX This is an extremely bogus implementations.
+ */
+struct hostent *
+gethostbyaddr_r(addr, len, af, he, buf, buflen, errorp)
+	const char *addr;	/* XXX should have been def'd as u_char! */
+	int len, af;
+	struct hostent * he;
+	char * buf;
+	int buflen;
+	int * errorp;
+{
+	struct hostent * res;
+
+	res = gethostbyaddr(addr, len, af);
+	*errorp = h_errno;
+	if (res == NULL)
+		return NULL;
+	memcpy(he, res, sizeof *he); /* XXX not sufficient */
+	return he;
+}
+
+/* XXX RFC2133 expects a gethostbyname2_r() -- unimplemented */
+#endif
+
+_THREAD_PRIVATE_MUTEX(gethostnamadr)
+
 struct hostent *
 gethostbyname(name)
 	const char *name;
@@ -430,15 +486,19 @@ gethostbyname(name)
 	struct hostent *hp;
 	extern struct hostent *_gethtbyname2();
 
+	_THREAD_PRIVATE_MUTEX_LOCK(gethostnamadr);
 	if ((_res.options & RES_INIT) == 0 && res_init() == -1)
-		return (_gethtbyname2(name, AF_INET));
+		hp = _gethtbyname2(name, AF_INET);
 
-	if (_res.options & RES_USE_INET6) {
+	else if (_res.options & RES_USE_INET6) {
 		hp = gethostbyname2(name, AF_INET6);
-		if (hp)
-			return (hp);
+		if (hp == NULL)
+			hp = gethostbyname2(name, AF_INET);
 	}
-	return (gethostbyname2(name, AF_INET));
+	else
+		hp = gethostbyname2(name, AF_INET);
+	_THREAD_PRIVATE_MUTEX_UNLOCK(gethostnamadr);
+	return hp;
 }
 
 struct hostent *
@@ -599,9 +659,14 @@ gethostbyaddr(addr, len, af)
 	char qbuf[MAXDNAME+1], *qp;
 	extern struct hostent *_gethtbyaddr(), *_yp_gethtbyaddr();
 	char lookups[MAXDNSLUS];
+	struct hostent *res;
 	
-	if ((_res.options & RES_INIT) == 0 && res_init() == -1)
-		return (_gethtbyaddr(addr, len, af));
+	_THREAD_PRIVATE_MUTEX_LOCK(gethostnamadr);
+	if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
+		res = _gethtbyaddr(addr, len, af);
+		_THREAD_PRIVATE_MUTEX_UNLOCK(gethostnamadr);
+		return (res);
+	}
 
 	if (af == AF_INET6 && len == IN6ADDRSZ &&
 	    (!bcmp(uaddr, mapped, sizeof mapped) ||
@@ -622,11 +687,13 @@ gethostbyaddr(addr, len, af)
 	default:
 		errno = EAFNOSUPPORT;
 		h_errno = NETDB_INTERNAL;
+		_THREAD_PRIVATE_MUTEX_UNLOCK(gethostnamadr);
 		return (NULL);
 	}
 	if (size != len) {
 		errno = EINVAL;
 		h_errno = NETDB_INTERNAL;
+		_THREAD_PRIVATE_MUTEX_UNLOCK(gethostnamadr);
 		return (NULL);
 	}
 	switch (af) {
@@ -692,6 +759,7 @@ gethostbyaddr(addr, len, af)
 			break;
 		}
 	}
+	_THREAD_PRIVATE_MUTEX_UNLOCK(gethostnamadr);
 	/* XXX h_errno not correct in all cases... */
 	return (hp);
 }
diff --git a/lib/libc/net/getservbyname.c b/lib/libc/net/getservbyname.c
index 25f0e27d06a..7375c894042 100644
--- a/lib/libc/net/getservbyname.c
+++ b/lib/libc/net/getservbyname.c
@@ -32,21 +32,28 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: getservbyname.c,v 1.3 1997/07/09 01:08:34 millert Exp $";
+static char rcsid[] = "$OpenBSD: getservbyname.c,v 1.4 1998/11/20 11:18:44 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <netdb.h>
 #include <string.h>
+#include "thread_private.h"
 
 extern int _serv_stayopen;
 
+_THREAD_PRIVATE_MUTEX(getservbyname_r)
+
 struct servent *
-getservbyname(name, proto)
+getservbyname_r(name, proto, se, buf, buflen)
 	const char *name, *proto;
+	struct servent *se;
+	char *buf;
+	int buflen;
 {
 	register struct servent *p;
 	register char **cp;
 
+	_THREAD_PRIVATE_MUTEX_LOCK(getservbyname_r);
 	setservent(_serv_stayopen);
 	while ((p = getservent())) {
 		if (strcmp(name, p->s_name) == 0)
@@ -61,5 +68,20 @@ gotname:
 	}
 	if (!_serv_stayopen)
 		endservent();
+	_THREAD_PRIVATE_MUTEX_UNLOCK(getservbyname_r);
 	return (p);
 }
+
+struct servent *getservbyname(name, proto)
+	const char *name, *proto;
+{
+	_THREAD_PRIVATE_KEY(getservbyname)
+	static char buf[4096];
+	char *bufp = (char*)_THREAD_PRIVATE(getservbyname, buf, NULL);
+
+	if (bufp == NULL)
+		return (NULL);
+	return getservbyname_r(name, proto, (struct servent*) bufp, 
+		bufp + sizeof(struct servent), 
+		sizeof buf - sizeof(struct servent) );
+}
diff --git a/lib/libc/nls/Makefile.inc b/lib/libc/nls/Makefile.inc
index e515e8c51d5..ac8eabe2d36 100644
--- a/lib/libc/nls/Makefile.inc
+++ b/lib/libc/nls/Makefile.inc
@@ -1,6 +1,6 @@
-#	$OpenBSD: Makefile.inc,v 1.3 1996/08/19 08:29:58 tholo Exp $
+#	$OpenBSD: Makefile.inc,v 1.4 1998/11/20 11:18:45 d Exp $
 
-.PATH: ${.CURDIR}/nls
+.PATH: ${LIBCSRCDIR}/nls
 
 SRCS+=	catclose.c catgets.c catopen.c 
 MAN+=	catclose.3 catgets.3 catopen.3
diff --git a/lib/libc/quad/Makefile.inc b/lib/libc/quad/Makefile.inc
index b2373026187..b13c9be1d2f 100644
--- a/lib/libc/quad/Makefile.inc
+++ b/lib/libc/quad/Makefile.inc
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.inc,v 1.2 1996/08/19 08:30:12 tholo Exp $
+#	$OpenBSD: Makefile.inc,v 1.3 1998/11/20 11:18:45 d Exp $
 
 # Quad support
 SRCS+=	adddi3.c anddi3.c ashldi3.c ashrdi3.c cmpdi2.c divdi3.c fixdfdi.c \
@@ -7,4 +7,4 @@ SRCS+=	adddi3.c anddi3.c ashldi3.c ashrdi3.c cmpdi2.c divdi3.c fixdfdi.c \
 	negdi2.c notdi2.c qdivrem.c subdi3.c ucmpdi2.c udivdi3.c umoddi3.c \
 	xordi3.c
 
-.PATH: ${.CURDIR}/arch/${MACHINE_ARCH}/quad ${.CURDIR}/quad
+.PATH: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/quad ${LIBCSRCDIR}/quad
diff --git a/lib/libc/regex/Makefile.inc b/lib/libc/regex/Makefile.inc
index f4a8f687923..4a786818f42 100644
--- a/lib/libc/regex/Makefile.inc
+++ b/lib/libc/regex/Makefile.inc
@@ -1,8 +1,8 @@
-#	$OpenBSD: Makefile.inc,v 1.3 1997/04/28 20:44:55 millert Exp $
+#	$OpenBSD: Makefile.inc,v 1.4 1998/11/20 11:18:46 d Exp $
 #	@(#)Makefile.inc	8.1 (Berkeley) 6/4/93
 
 # regex sources
-.PATH: ${.CURDIR}/regex
+.PATH: ${LIBCSRCDIR}/regex
 
 CFLAGS+=-DPOSIX_MISTAKE
 
diff --git a/lib/libc/rpc/Makefile.inc b/lib/libc/rpc/Makefile.inc
index 2265f6a8e0f..d4ea29b4c91 100644
--- a/lib/libc/rpc/Makefile.inc
+++ b/lib/libc/rpc/Makefile.inc
@@ -1,7 +1,7 @@
-#	$OpenBSD: Makefile.inc,v 1.7 1998/08/29 21:11:47 deraadt Exp $
+#	$OpenBSD: Makefile.inc,v 1.8 1998/11/20 11:18:47 d Exp $
 
 # librpc sources
-.PATH:	${.CURDIR}/arch/${MACHINE}/rpc ${.CURDIR}/rpc
+.PATH:	${LIBCSRCDIR}/arch/${MACHINE}/rpc ${LIBCSRCDIR}/rpc
 
 SRCS+=	auth_none.c auth_unix.c  authunix_prot.c bindresvport.c \
 	clnt_generic.c clnt_perror.c clnt_raw.c clnt_simple.c clnt_tcp.c \
diff --git a/lib/libc/stdio/Makefile.inc b/lib/libc/stdio/Makefile.inc
index c83779e225e..18eb2722926 100644
--- a/lib/libc/stdio/Makefile.inc
+++ b/lib/libc/stdio/Makefile.inc
@@ -1,7 +1,7 @@
-#	$OpenBSD: Makefile.inc,v 1.7 1998/08/30 22:19:38 millert Exp $
+#	$OpenBSD: Makefile.inc,v 1.8 1998/11/20 11:18:48 d Exp $
 
 # stdio sources
-.PATH: ${.CURDIR}/stdio
+.PATH: ${LIBCSRCDIR}/stdio
 
 CFLAGS+=-DFLOATING_POINT
 
@@ -14,7 +14,7 @@ SRCS+=	asprintf.c clrerr.c fclose.c fdopen.c feof.c ferror.c fflush.c fgetc.c \
 	scanf.c setbuf.c setbuffer.c setvbuf.c snprintf.c sprintf.c sscanf.c \
 	stdio.c tempnam.c tmpfile.c tmpnam.c ungetc.c vasprintf.c vfprintf.c \
 	vfscanf.c vprintf.c vscanf.c vsnprintf.c vsprintf.c vsscanf.c \
-	wbuf.c wsetup.c
+	wbuf.c wsetup.c flockfile.c
 
 MAN+=	fclose.3 ferror.3 fflush.3 fgetln.3 fgets.3 fopen.3 fputs.3 \
 	fread.3 fseek.3 funopen.3 getc.3 mktemp.3 perror.3 printf.3 putc.3 \
diff --git a/lib/libc/stdio/clrerr.c b/lib/libc/stdio/clrerr.c
index 90de2ddaaca..1bd72b93fb5 100644
--- a/lib/libc/stdio/clrerr.c
+++ b/lib/libc/stdio/clrerr.c
@@ -35,7 +35,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: clrerr.c,v 1.2 1996/08/19 08:32:17 tholo Exp $";
+static char rcsid[] = "$OpenBSD: clrerr.c,v 1.3 1998/11/20 11:18:48 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <stdio.h>
@@ -45,5 +45,7 @@ void
 clearerr(fp)
 	FILE *fp;
 {
+	flockfile(fp);
 	__sclearerr(fp);
+	funlockfile(fp);
 }
diff --git a/lib/libc/stdio/flockfile.c b/lib/libc/stdio/flockfile.c
new file mode 100644
index 00000000000..d720aee991a
--- /dev/null
+++ b/lib/libc/stdio/flockfile.c
@@ -0,0 +1,49 @@
+/*	$OpenBSD: flockfile.c,v 1.1 1998/11/20 11:18:48 d Exp $	*/
+
+#include <stdio.h>
+#include "thread_private.h"
+
+#ifndef _THREAD_SAFE
+
+/*
+ * Subroutine versions of the macros in <stdio.h>
+ * Note that these are all no-ops because libc does not do threads.
+ */
+
+#undef flockfile
+#undef ftrylockfile
+#undef funlockfile
+#undef _flockfile_debug
+
+void
+flockfile(fp)
+	FILE * fp;
+{
+}
+
+int
+ftrylockfile(fp)
+	FILE * fp;
+{
+	return 0;
+}
+
+void
+funlockfile(fp)
+	FILE * fp;
+{
+}
+
+void
+_flockfile_debug(fp, fname, lineno)
+	FILE * fp;
+	const char * fname;
+	int lineno;
+{
+}
+
+#else /* _THREAD_SAFE */
+
+/* Actual implementation of file locking in libc_r/uthread/uthread_file.c */
+
+#endif /* _THREAD_SAFE */
diff --git a/lib/libc/stdio/getc.c b/lib/libc/stdio/getc.c
index ff4a5168a3f..ce990968202 100644
--- a/lib/libc/stdio/getc.c
+++ b/lib/libc/stdio/getc.c
@@ -35,12 +35,24 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: getc.c,v 1.2 1996/08/19 08:32:51 tholo Exp $";
+static char rcsid[] = "$OpenBSD: getc.c,v 1.3 1998/11/20 11:18:48 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <stdio.h>
 
 /*
+ * A subroutine version of the macro getc_unlocked.
+ */
+#undef getc_unlocked
+
+int
+getc_unlocked(fp)
+	FILE *fp;
+{
+	return (__sgetc(fp));
+}
+
+/*
  * A subroutine version of the macro getc.
  */
 #undef getc
@@ -49,5 +61,10 @@ int
 getc(fp)
 	register FILE *fp;
 {
-	return (__sgetc(fp));
+	int c;
+
+	flockfile(fp);
+	c = __sgetc(fp);
+	funlockfile(fp);
+	return (c);
 }
diff --git a/lib/libc/stdio/putc.c b/lib/libc/stdio/putc.c
index b43af508a55..f9a23b2cd41 100644
--- a/lib/libc/stdio/putc.c
+++ b/lib/libc/stdio/putc.c
@@ -35,7 +35,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: putc.c,v 1.3 1996/10/28 05:32:55 tholo Exp $";
+static char rcsid[] = "$OpenBSD: putc.c,v 1.4 1998/11/20 11:18:48 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <stdio.h>
@@ -43,11 +43,12 @@ static char rcsid[] = "$OpenBSD: putc.c,v 1.3 1996/10/28 05:32:55 tholo Exp $";
 #include "local.h"
 
 /*
- * A subroutine version of the macro putc.
+ * A subroutine version of the macro putc_unlocked.
  */
-#undef putc
+#undef putc_unlocked
 
-putc(c, fp)
+int
+putc_unlocked(c, fp)
 	int c;
 	register FILE *fp;
 {
@@ -57,3 +58,21 @@ putc(c, fp)
 	}
 	return (__sputc(c, fp));
 }
+
+/*
+ * A subroutine version of the macro putc.
+ */
+#undef putc
+
+int
+putc(c, fp)
+	int c;
+	FILE *fp;
+{
+	int ret;
+
+	flockfile(fp);
+	ret = putc_unlocked(c, fp);
+	funlockfile(fp);
+	return (ret);
+}
diff --git a/lib/libc/stdlib/Makefile.inc b/lib/libc/stdlib/Makefile.inc
index bdd5280ddec..3191f08328c 100644
--- a/lib/libc/stdlib/Makefile.inc
+++ b/lib/libc/stdlib/Makefile.inc
@@ -1,7 +1,7 @@
 #	$OpenBDS: Makefile.inc,v 1.6 1996/08/21 03:47:21 tholo Exp $
 
 # stdlib sources
-.PATH: ${.CURDIR}/arch/${MACHINE_ARCH}/stdlib ${.CURDIR}/stdlib
+.PATH: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/stdlib ${LIBCSRCDIR}/stdlib
 
 SRCS+=	a64l.c abort.c atexit.c atoi.c atof.c atol.c bsearch.c calloc.c \
 	cfree.c exit.c getenv.c getopt.c getsubopt.c heapsort.c l64a.c \
diff --git a/lib/libc/stdlib/abort.c b/lib/libc/stdlib/abort.c
index 4ea8a2ca4b7..4cc6257acb9 100644
--- a/lib/libc/stdlib/abort.c
+++ b/lib/libc/stdlib/abort.c
@@ -32,12 +32,13 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char *rcsid = "$OpenBSD: abort.c,v 1.5 1997/06/22 20:21:25 tholo Exp $";
+static char *rcsid = "$OpenBSD: abort.c,v 1.6 1998/11/20 11:18:49 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <signal.h>
 #include <stdlib.h>
 #include <unistd.h>
+#include "thread_private.h"
 
 void (*__cleanup)();
 
@@ -54,7 +55,11 @@ abort()
 	 * any errors -- X311J doesn't allow abort to return anyway.
 	 */
 	sigdelset(&mask, SIGABRT);
+#ifdef _THREAD_SAFE
+	(void)_thread_sys_sigprocmask(SIG_SETMASK, &mask, (sigset_t *)NULL);
+#else  _THREAD_SAFE
 	(void)sigprocmask(SIG_SETMASK, &mask, (sigset_t *)NULL);
+#endif _THREAD_SAFE
 
 	/*
 	 * POSIX requires we flush stdio buffers on abort
@@ -71,7 +76,11 @@ abort()
 	 * it again, only harder.
 	 */
 	(void)signal(SIGABRT, SIG_DFL);
+#ifdef _THREAD_SAFE
+	(void)_thread_sys_sigprocmask(SIG_SETMASK, &mask, (sigset_t *)NULL);
+#else  _THREAD_SAFE
 	(void)sigprocmask(SIG_SETMASK, &mask, (sigset_t *)NULL);
+#endif _THREAD_SAFE
 	(void)kill(getpid(), SIGABRT);
 	exit(1);
 }
diff --git a/lib/libc/stdlib/exit.c b/lib/libc/stdlib/exit.c
index e358c94fd66..bc7fd395ca3 100644
--- a/lib/libc/stdlib/exit.c
+++ b/lib/libc/stdlib/exit.c
@@ -32,7 +32,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char *rcsid = "$OpenBSD: exit.c,v 1.2 1996/08/19 08:33:30 tholo Exp $";
+static char *rcsid = "$OpenBSD: exit.c,v 1.3 1998/11/20 11:18:50 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <stdlib.h>
@@ -42,6 +42,15 @@ static char *rcsid = "$OpenBSD: exit.c,v 1.2 1996/08/19 08:33:30 tholo Exp $";
 void (*__cleanup)();
 
 /*
+ * This variable is zero until a process has created a thread.
+ * It is used to avoid calling locking functions in libc when they
+ * are not required. By default, libc is intended to be(come)
+ * thread-safe, but without a (significant) penalty to non-threaded
+ * processes.
+ */
+int     __isthreaded    = 0;
+
+/*
  * Exit, flushing stdio buffers if necessary.
  */
 void
diff --git a/lib/libc/stdlib/malloc.c b/lib/libc/stdlib/malloc.c
index d1d87597918..ecbf93dc489 100644
--- a/lib/libc/stdlib/malloc.c
+++ b/lib/libc/stdlib/malloc.c
@@ -8,7 +8,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: malloc.c,v 1.32 1998/08/06 16:26:32 millert Exp $";
+static char rcsid[] = "$OpenBSD: malloc.c,v 1.33 1998/11/20 11:18:50 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 /*
@@ -87,15 +87,27 @@ static char rcsid[] = "$OpenBSD: malloc.c,v 1.32 1998/08/06 16:26:32 millert Exp
 #endif /* __OpenBSD__ */
 
 #ifdef _THREAD_SAFE
-#include <pthread.h>
-static pthread_mutex_t malloc_lock;
-#define THREAD_LOCK()		pthread_mutex_lock(&malloc_lock)
-#define THREAD_UNLOCK()		pthread_mutex_unlock(&malloc_lock)
-#define THREAD_LOCK_INIT()	pthread_mutex_init(&malloc_lock, 0);
+# include "thread_private.h"
+# if 0
+   /* kernel threads */
+#  include <pthread.h>
+   static pthread_mutex_t malloc_lock;
+#  define THREAD_LOCK()		pthread_mutex_lock(&malloc_lock)
+#  define THREAD_UNLOCK()	pthread_mutex_unlock(&malloc_lock)
+#  define THREAD_LOCK_INIT()	pthread_mutex_init(&malloc_lock, 0);
+# else
+   /* user threads */
+#  include "spinlock.h"
+   static spinlock_t malloc_lock = _SPINLOCK_INITIALIZER;
+#  define THREAD_LOCK()		if (__isthreaded) _SPINLOCK(&malloc_lock)
+#  define THREAD_UNLOCK()	if (__isthreaded) _SPINUNLOCK(&malloc_lock)
+#  define THREAD_LOCK_INIT()	
+# endif
 #else
-#define THREAD_LOCK()
-#define THREAD_UNLOCK()
-#define THREAD_LOCK_INIT()
+  /* no threads */
+# define THREAD_LOCK()
+# define THREAD_UNLOCK()
+# define THREAD_LOCK_INIT()
 #endif
 
 /*
diff --git a/lib/libc/stdlib/rand.3 b/lib/libc/stdlib/rand.3
index 32d32761f19..28496ec12aa 100644
--- a/lib/libc/stdlib/rand.3
+++ b/lib/libc/stdlib/rand.3
@@ -33,7 +33,7 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.\"	$OpenBSD: rand.3,v 1.4 1998/07/05 19:54:22 millert Exp $
+.\"	$OpenBSD: rand.3,v 1.5 1998/11/20 11:18:50 d Exp $
 .\"
 .Dd June 29, 1991
 .Dt RAND 3
@@ -48,6 +48,8 @@
 .Fn srand "unsigned seed"
 .Ft int
 .Fn rand void
+.Ft int
+.Fn rand_r "unsigned int *seed"
 .Sh DESCRIPTION
 .Bf -symbolic
 These interfaces are obsoleted by
@@ -73,6 +75,14 @@ with the same seed value.
 .Pp
 If no seed value is provided, the functions are automatically
 seeded with a value of 1.
+.Pp
+The
+.Fn rand_r
+is a thread-safe version of
+.Fn rand .
+Storage for the seed must be provided through the
+.Ar seed
+argument, and needs to have been initialized by the caller.
 .Sh SEE ALSO
 .Xr arc4random 3 ,
 .Xr rand48 3 ,
@@ -85,3 +95,10 @@ and
 functions
 conform to
 .St -ansiC .
+.Pp
+The
+.Fn rand_r
+function
+conforms to ISO/IEC 9945-1 ANSI/IEEE
+.Pq Dq Tn POSIX
+Std 1003.1c Draft 10.
diff --git a/lib/libc/stdlib/rand.c b/lib/libc/stdlib/rand.c
index f270ffd9868..61fb66e5eca 100644
--- a/lib/libc/stdlib/rand.c
+++ b/lib/libc/stdlib/rand.c
@@ -32,7 +32,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char *rcsid = "$OpenBSD: rand.c,v 1.2 1996/08/19 08:33:44 tholo Exp $";
+static char *rcsid = "$OpenBSD: rand.c,v 1.3 1998/11/20 11:18:50 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <sys/types.h>
@@ -41,9 +41,17 @@ static char *rcsid = "$OpenBSD: rand.c,v 1.2 1996/08/19 08:33:44 tholo Exp $";
 static u_long next = 1;
 
 int
+rand_r(seed)
+u_int *seed;
+{
+	*seed = *seed * 1103515245 + 12345;
+	return (u_int)(*seed / 65536) % ((u_int)RAND_MAX + 1);
+}
+
+int
 rand()
 {
-	return ((next = next * 1103515245 + 12345) % ((u_int)RAND_MAX + 1));
+	return rand_r(&next);
 }
 
 void
diff --git a/lib/libc/string/Makefile.inc b/lib/libc/string/Makefile.inc
index 076db78945a..78eee7efa57 100644
--- a/lib/libc/string/Makefile.inc
+++ b/lib/libc/string/Makefile.inc
@@ -1,7 +1,7 @@
-#	$OpenBSD: Makefile.inc,v 1.5 1998/07/01 01:29:44 millert Exp $
+#	$OpenBSD: Makefile.inc,v 1.6 1998/11/20 11:18:51 d Exp $
 
 # string sources
-.PATH: ${.CURDIR}/arch/${MACHINE_ARCH}/string ${.CURDIR}/string
+.PATH: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/string ${LIBCSRCDIR}/string
 
 SRCS+=	bm.c memccpy.c strcasecmp.c strcoll.c strdup.c strerror.c \
 	strlcat.c strlcpy.c strmode.c strsignal.c strtok.c strxfrm.c \
@@ -16,7 +16,7 @@ SRCS+=	bm.c memccpy.c strcasecmp.c strcoll.c strdup.c strerror.c \
 # m-d Makefile.inc may include sources for:
 #	memcpy() memmove() strchr() strrchr()
 
-.include "${.CURDIR}/arch/${MACHINE_ARCH}/string/Makefile.inc"
+.include "${LIBCSRCDIR}/arch/${MACHINE_ARCH}/string/Makefile.inc"
 
 # if no machine specific memmove(3), build one out of bcopy(3).
 .if empty(SRCS:Mmemmove.S)
@@ -100,19 +100,19 @@ LOBJS+=	memmove.ln memcpy.ln strchr.ln strrchr.ln
 
 memmove.ln: bcopy.c
 	lint ${LINTFLAGS} -DMEMMOVE ${CFLAGS:M-[IDU]*} -i -o ${.TARGET} \
-		${.CURDIR}/string/bcopy.c
+		${LIBCSRCDIR}/string/bcopy.c
 
 memcpy.ln: bcopy.c
 	lint ${LINTFLAGS} -DMEMCOPY ${CFLAGS:M-[IDU]*} -i -o ${.TARGET} \
-		${.CURDIR}/string/bcopy.c
+		${LIBCSRCDIR}/string/bcopy.c
 
 strchr.ln: index.c
 	lint ${LINTFLAGS} -DSTRCHR ${CFLAGS:M-[IDU]*} -i -o ${.TARGET} \
-		${.CURDIR}/string/index.c
+		${LIBCSRCDIR}/string/index.c
 
 strrchr.ln: rindex.c
 	lint ${LINTFLAGS} -DSTRRCHR ${CFLAGS:M-[IDU]*} -i -o ${.TARGET} \
-		${.CURDIR}/string/rindex.c
+		${LIBCSRCDIR}/string/rindex.c
 
 MAN+=	bm.3 bcmp.3 bcopy.3 bstring.3 bzero.3 ffs.3 index.3 memccpy.3 memchr.3 \
 	memcmp.3 memcpy.3 memmove.3 memset.3 rindex.3 strcasecmp.3 strcat.3 \
diff --git a/lib/libc/sys/Makefile.inc b/lib/libc/sys/Makefile.inc
index 801f728f13d..3bc64a19d3e 100644
--- a/lib/libc/sys/Makefile.inc
+++ b/lib/libc/sys/Makefile.inc
@@ -1,21 +1,21 @@
-#	$OpenBSD: Makefile.inc,v 1.26 1998/09/18 00:48:35 art Exp $
+#	$OpenBSD: Makefile.inc,v 1.27 1998/11/20 11:18:52 d Exp $
 #	$NetBSD: Makefile.inc,v 1.35 1995/10/16 23:49:07 jtc Exp $
 #	@(#)Makefile.inc	8.1 (Berkeley) 6/17/93
 
 # sys sources
-.PATH: ${.CURDIR}/arch/${MACHINE_ARCH}/sys ${.CURDIR}/sys
+.PATH: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/sys ${LIBCSRCDIR}/sys
 
 # modules with non-default implementations on at least one architecture:
 SRCS+=	Ovfork.S brk.S cerror.S exect.S fork.S pipe.S ptrace.S \
-	sbrk.S setlogin.S sigpending.S sigprocmask.S sigreturn.S \
+	sbrk.S sigpending.S sigprocmask.S sigreturn.S \
 	sigsuspend.S syscall.S
 
 LSRCS+=	Lint_Ovfork.c Lint_brk.c Lint_exect.c Lint_fork.c \
-	Lint_pipe.c Lint_ptrace.c Lint_sbrk.c Lint_setlogin.c \
+	Lint_pipe.c Lint_ptrace.c Lint_sbrk.c \
 	Lint_sigpending.c Lint_sigprocmask.c Lint_sigreturn.c \
 	Lint_sigsuspend.c Lint_syscall.c
 DPSRCS+= Lint_Ovfork.c Lint_brk.c Lint_exect.c Lint_fork.c \
-	Lint_pipe.c Lint_ptrace.c Lint_sbrk.c Lint_setlogin.c \
+	Lint_pipe.c Lint_ptrace.c Lint_sbrk.c \
 	Lint_sigpending.c Lint_sigprocmask.c Lint_sigreturn.c \
 	Lint_sigsuspend.c Lint_syscall.c
 
@@ -58,13 +58,13 @@ ASM=	accept.o access.o acct.o adjtime.o bind.o chdir.o chflags.o chmod.o \
 PASM=	${ASM:.o=.po}
 SASM=	${ASM:.o=.so}
 
-PSEUDO=	_exit.o _getlogin.o
+PSEUDO=	_exit.o _getlogin.o _setlogin.o
 PPSEUDO=${PSEUDO:.o=.po}
 SPSEUDO=${PSEUDO:.o=.so}
 
 OBJS+=	${ASM} ${PSEUDO}
 
-${PASM}: ${.CURDIR}/arch/${MACHINE_ARCH}/SYS.h /usr/include/sys/syscall.h
+${PASM}: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/SYS.h /usr/include/sys/syscall.h
 	@echo creating ${.TARGET}
 	@printf '#include "SYS.h"\nRSYSCALL(${.PREFIX})\n' | \
 	    ${CPP} -DPROF ${CFLAGS:M-[ID]*} ${AINC} | ${AS} -o ${.TARGET}.o
@@ -72,25 +72,25 @@ ${PASM}: ${.CURDIR}/arch/${MACHINE_ARCH}/SYS.h /usr/include/sys/syscall.h
 	@rm -f ${.TARGET}.o
 
 .if (${MACHINE_ARCH} != "mips")
-${SASM}: ${.CURDIR}/arch/${MACHINE_ARCH}/SYS.h /usr/include/sys/syscall.h
+${SASM}: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/SYS.h /usr/include/sys/syscall.h
 	@echo creating ${.TARGET}
 	@printf '#include "SYS.h"\nRSYSCALL(${.PREFIX})\n' | \
 	    ${CPP} -DPIC ${CFLAGS:M-[ID]*} ${AINC} | ${AS} -k -o ${.TARGET}
 .else
-${SASM}: ${.CURDIR}/arch/${MACHINE_ARCH}/SYS.h /usr/include/sys/syscall.h
+${SASM}: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/SYS.h /usr/include/sys/syscall.h
 	@echo creating ${.TARGET}
 	@printf '#include "SYS.h"\nRSYSCALL(${.PREFIX})\n' | \
 	    ${CPP} -DPIC ${CFLAGS:M-[ID]*} ${AINC} | ${AS} -o ${.TARGET}
 .endif
 
-${ASM}: ${.CURDIR}/arch/${MACHINE_ARCH}/SYS.h /usr/include/sys/syscall.h
+${ASM}: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/SYS.h /usr/include/sys/syscall.h
 	@echo creating ${.TARGET}
 	@printf '#include "SYS.h"\nRSYSCALL(${.PREFIX})\n' | \
 	    ${CPP} ${CFLAGS:M-[ID]*} ${AINC} | ${AS} -o ${.TARGET}.o
 	@${LD} -x -r ${.TARGET}.o -o ${.TARGET}
 	@rm -f ${.TARGET}.o
 
-${PPSEUDO}: ${.CURDIR}/arch/${MACHINE_ARCH}/SYS.h /usr/include/sys/syscall.h
+${PPSEUDO}: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/SYS.h /usr/include/sys/syscall.h
 	@echo creating ${.TARGET}
 	@printf '#include "SYS.h"\nPSEUDO(${.PREFIX},${.PREFIX:S/_//})\n' | \
 	    ${CPP} -DPROF ${CFLAGS:M-[ID]*} ${AINC} | ${AS} -o ${.TARGET}.o
@@ -98,18 +98,18 @@ ${PPSEUDO}: ${.CURDIR}/arch/${MACHINE_ARCH}/SYS.h /usr/include/sys/syscall.h
 	@rm -f ${.TARGET}.o
 
 .if (${MACHINE_ARCH} != "mips")
-${SPSEUDO}: ${.CURDIR}/arch/${MACHINE_ARCH}/SYS.h /usr/include/sys/syscall.h
+${SPSEUDO}: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/SYS.h /usr/include/sys/syscall.h
 	@echo creating ${.TARGET}
 	@printf '#include "SYS.h"\nPSEUDO(${.PREFIX},${.PREFIX:S/_//})\n' | \
 	    ${CPP} -DPIC ${CFLAGS:M-[ID]*} ${AINC} | ${AS} -k -o ${.TARGET}
 .else
-${SPSEUDO}: ${.CURDIR}/arch/${MACHINE_ARCH}/SYS.h /usr/include/sys/syscall.h
+${SPSEUDO}: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/SYS.h /usr/include/sys/syscall.h
 	@echo creating ${.TARGET}
 	@printf '#include "SYS.h"\nPSEUDO(${.PREFIX},${.PREFIX:S/_//})\n' | \
 	    ${CPP} -DPIC ${CFLAGS:M-[ID]*} ${AINC} | ${AS} -o ${.TARGET}
 .endif
 
-${PSEUDO}: ${.CURDIR}/arch/${MACHINE_ARCH}/SYS.h /usr/include/sys/syscall.h
+${PSEUDO}: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/SYS.h /usr/include/sys/syscall.h
 	@echo creating ${.TARGET}
 	@printf '#include "SYS.h"\nPSEUDO(${.PREFIX},${.PREFIX:S/_//})\n' | \
 	    ${CPP} ${CFLAGS:M-[ID]*} ${AINC} | ${AS} -o ${.TARGET}.o
@@ -124,22 +124,22 @@ DPSRCS+= LintSysNormal.c
 
 CLEANFILES+= LintSysNormal.c LintSysNoerr.c LintSysPseudo.c
 
-LintSysNormal.c: ${.CURDIR}/sys/makelintstub.sh \
+LintSysNormal.c: ${LIBCSRCDIR}/sys/makelintstub.sh \
     ${DESTDIR}/usr/include/sys/syscall.h
 	@echo creating ${.TARGET}
-	@sh ${.CURDIR}/sys/makelintstub.sh -o ${.TARGET} \
+	@sh ${LIBCSRCDIR}/sys/makelintstub.sh -o ${.TARGET} \
 	    -s ${DESTDIR}/usr/include/sys/syscall.h ${ASM}
 
-LintSysNoerr.c: ${.CURDIR}/sys/makelintstub.sh \
+LintSysNoerr.c: ${LIBCSRCDIR}/sys/makelintstub.sh \
     ${DESTDIR}/usr/include/sys/syscall.h
 	@echo creating ${.TARGET}
-	@sh ${.CURDIR}/sys/makelintstub.sh -o ${.TARGET} -n \
+	@sh ${LIBCSRCDIR}/sys/makelintstub.sh -o ${.TARGET} -n \
 	    -s ${DESTDIR}/usr/include/sys/syscall.h ${NOERR}
 
-LintSysPseudoNoerr.c: ${.CURDIR}/sys/makelintstub.sh \
+LintSysPseudoNoerr.c: ${LIBCSRCDIR}/sys/makelintstub.sh \
     ${DESTDIR}/usr/include/sys/syscall.h
 	@echo creating ${.TARGET}
-	@sh ${.CURDIR}/sys/makelintstub.sh -o ${.TARGET} -p \
+	@sh ${LIBCSRCDIR}/sys/makelintstub.sh -o ${.TARGET} -p \
 	    -s ${DESTDIR}/usr/include/sys/syscall.h ${PSEUDONOERR}
 
 MAN+=	accept.2 access.2 acct.2 adjtime.2 bind.2 brk.2 chdir.2 chflags.2 \
diff --git a/lib/libc/sys/ftruncate.c b/lib/libc/sys/ftruncate.c
index 108c056185d..c7f4bf3a6b6 100644
--- a/lib/libc/sys/ftruncate.c
+++ b/lib/libc/sys/ftruncate.c
@@ -32,11 +32,12 @@
  */
 
 #if defined(SYSLIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: ftruncate.c,v 1.6 1997/04/26 08:50:12 tholo Exp $";
+static char rcsid[] = "$OpenBSD: ftruncate.c,v 1.7 1998/11/20 11:18:52 d Exp $";
 #endif /* SYSLIBC_SCCS and not lint */
 
 #include <sys/types.h>
 #include <sys/syscall.h>
+#include "thread_private.h"
 
 #ifdef lint
 quad_t __syscall(quad_t, ...);
@@ -51,6 +52,13 @@ ftruncate(fd, length)
 	int	fd;
 	off_t	length;
 {
+	int retval;
 
-	return(__syscall((quad_t)SYS_ftruncate, fd, 0, length));
+	if (_FD_LOCK(fd, FD_RDWR, NULL) != 0) {
+		retval = -1;
+	} else {
+		retval = __syscall((quad_t)SYS_ftruncate, fd, 0, length);
+		_FD_UNLOCK(fd, FD_RDWR);
+	}
+	return retval;
 }
diff --git a/lib/libc/sys/lseek.c b/lib/libc/sys/lseek.c
index 62f7d581b9e..12d2a98c86f 100644
--- a/lib/libc/sys/lseek.c
+++ b/lib/libc/sys/lseek.c
@@ -32,11 +32,12 @@
  */
 
 #if defined(SYSLIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: lseek.c,v 1.5 1997/04/26 08:50:12 tholo Exp $";
+static char rcsid[] = "$OpenBSD: lseek.c,v 1.6 1998/11/20 11:18:53 d Exp $";
 #endif /* SYSLIBC_SCCS and not lint */
 
 #include <sys/types.h>
 #include <sys/syscall.h>
+#include "thread_private.h"
 
 /*
  * This function provides 64-bit offset padding that
@@ -49,6 +50,13 @@ lseek(fd, offset, whence)
 	int	whence;
 {
 	extern off_t __syscall();
+	off_t retval;
 
-	return(__syscall((quad_t)SYS_lseek, fd, 0, offset, whence));
+	if (_FD_LOCK(fd, FD_RDWR, NULL) != 0) {
+		retval = -1;
+	} else {
+		retval = __syscall((quad_t)SYS_lseek, fd, 0, offset, whence);
+		_FD_UNLOCK(fd, FD_RDWR);
+	}
+	return retval;
 }
diff --git a/lib/libc/termios/Makefile.inc b/lib/libc/termios/Makefile.inc
index 7ca8c61e7a5..14002b3d3bc 100644
--- a/lib/libc/termios/Makefile.inc
+++ b/lib/libc/termios/Makefile.inc
@@ -1,6 +1,6 @@
-#	$OpenBSD: Makefile.inc,v 1.2 1996/08/19 08:34:34 tholo Exp $
+#	$OpenBSD: Makefile.inc,v 1.3 1998/11/20 11:18:54 d Exp $
 
-.PATH:	${.CURDIR}/termios
+.PATH:	${LIBCSRCDIR}/termios
 
 SRCS+=	cfgetispeed.c cfgetospeed.c cfmakeraw.c cfsetispeed.c cfsetospeed.c \
 	cfsetspeed.c tcdrain.c tcflow.c tcflush.c tcgetattr.c tcgetpgrp.c \
diff --git a/lib/libc/time/Makefile.inc b/lib/libc/time/Makefile.inc
index 9da5655a284..58ca1bf782a 100644
--- a/lib/libc/time/Makefile.inc
+++ b/lib/libc/time/Makefile.inc
@@ -1,6 +1,6 @@
-#	$OpenBSD: Makefile.inc,v 1.4 1998/02/04 22:22:42 deraadt Exp $
+#	$OpenBSD: Makefile.inc,v 1.5 1998/11/20 11:18:55 d Exp $
 
-.PATH: ${.CURDIR}/time
+.PATH: ${LIBCSRCDIR}/time
 
 SRCS+=	asctime.c difftime.c localtime.c strftime.c strptime.c
 MAN+=	ctime.3 strftime.3 time2posix.3 tzfile.5 tzset.3 strptime.3
diff --git a/lib/libc/time/asctime.c b/lib/libc/time/asctime.c
index 690430a94b1..7b5257488cb 100644
--- a/lib/libc/time/asctime.c
+++ b/lib/libc/time/asctime.c
@@ -5,21 +5,23 @@
 
 #if defined(LIBC_SCCS) && !defined(lint) && !defined(NOID)
 static char elsieid[] = "@(#)asctime.c	7.8";
-static char rcsid[] = "$OpenBSD: asctime.c,v 1.4 1998/01/18 23:24:50 millert Exp $";
+static char rcsid[] = "$OpenBSD: asctime.c,v 1.5 1998/11/20 11:18:55 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 /*LINTLIBRARY*/
 
 #include "private.h"
 #include "tzfile.h"
+#include "thread_private.h"
 
 /*
 ** A la X3J11, with core dump avoidance.
 */
 
 char *
-asctime(timeptr)
+asctime_r(timeptr, result)
 register const struct tm *	timeptr;
+char *result;
 {
 	static const char	wday_name[][3] = {
 		"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
@@ -28,17 +30,10 @@ register const struct tm *	timeptr;
 		"Jan", "Feb", "Mar", "Apr", "May", "Jun",
 		"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
 	};
-	/*
-	** Big enough for something such as
-	** ??? ???-2147483648 -2147483648:-2147483648:-2147483648 -2147483648\n
-	** (two three-character abbreviations, five strings denoting integers,
-	** three explicit spaces, two explicit colons, a newline,
-	** and a trailing ASCII nul).
-	*/
-	static char		result[3 * 2 + 5 * INT_STRLEN_MAXIMUM(int) +
-					3 + 2 + 1 + 1];
+
 	register const char *	wn;
 	register const char *	mn;
+	int size;
 
 	if (timeptr->tm_wday < 0 || timeptr->tm_wday >= DAYSPERWEEK)
 		wn = "???";
@@ -51,10 +46,38 @@ register const struct tm *	timeptr;
 	**	"%.3s %.3s%3d %02.2d:%02.2d:%02.2d %d\n"
 	** Since the .2 in 02.2d is ignored, we drop it.
 	*/
-	(void) sprintf(result, "%.3s %.3s%3d %02d:%02d:%02d %d\n",
+	/*
+	 * P1003 8.3.5.2 says that asctime_r() can only assume at most
+	 * a 26 byte buffer.  *XXX*
+	 */
+	size = snprintf(result, 26, "%.3s %.3s%3d %02d:%02d:%02d %d\n",
 		wn, mn,
 		timeptr->tm_mday, timeptr->tm_hour,
 		timeptr->tm_min, timeptr->tm_sec,
 		TM_YEAR_BASE + timeptr->tm_year);
+	if (size >= 26)
+		return NULL;
 	return result;
 }
+
+/*
+ * Theoretically, the worst case string is of the form
+ * "www mmm-2147483648 -2147483648:-2147483648:-2147483648 -2147483648\n"
+ * but we only provide space for 26 since asctime_r won't use any more.
+ * "www mmmddd hh:mm:ss yyyy\n"
+ */
+char *
+asctime(timeptr)
+const struct tm *	timeptr;
+{
+
+	static char result[26];
+	_THREAD_PRIVATE_KEY(asctime)
+	char *resultp = (char*) _THREAD_PRIVATE(asctime, result, NULL);
+
+	if (resultp == NULL)
+		return NULL;
+	else
+		return asctime_r(timeptr, resultp);
+}
+
diff --git a/lib/libc/time/localtime.c b/lib/libc/time/localtime.c
index e8154d297ba..dc638321a7f 100644
--- a/lib/libc/time/localtime.c
+++ b/lib/libc/time/localtime.c
@@ -5,7 +5,7 @@
 
 #if defined(LIBC_SCCS) && !defined(lint) && !defined(NOID)
 static char elsieid[] = "@(#)localtime.c	7.64";
-static char rcsid[] = "$OpenBSD: localtime.c,v 1.13 1998/07/11 23:17:20 deraadt Exp $";
+static char rcsid[] = "$OpenBSD: localtime.c,v 1.14 1998/11/20 11:18:55 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 /*
@@ -19,6 +19,7 @@ static char rcsid[] = "$OpenBSD: localtime.c,v 1.13 1998/07/11 23:17:20 deraadt
 #include "private.h"
 #include "tzfile.h"
 #include "fcntl.h"
+#include "thread_private.h"
 
 /*
 ** SunOS 4.1.1 headers lack O_BINARY.
@@ -166,6 +167,8 @@ static struct state	gmtmem;
 static char		lcl_TZname[TZ_STRLEN_MAX + 1];
 static int		lcl_is_set;
 static int		gmt_is_set;
+_THREAD_PRIVATE_MUTEX(lcl);
+_THREAD_PRIVATE_MUTEX(gmt);
 
 char *			tzname[2] = {
 	wildabbr,
@@ -920,16 +923,9 @@ struct state * const	sp;
 	if (tzload(gmt, sp) != 0)
 		(void) tzparse(gmt, sp, TRUE);
 }
-
-#ifndef STD_INSPIRED
-/*
-** A non-static declaration of tzsetwall in a system header file
-** may cause a warning about this upcoming static declaration...
-*/
 static
-#endif /* !defined STD_INSPIRED */
 void
-tzsetwall P((void))
+tzsetwall_basic P((void))
 {
 	if (lcl_is_set < 0)
 		return;
@@ -949,14 +945,30 @@ tzsetwall P((void))
 	settzname();
 }
 
+#ifndef STD_INSPIRED
+/*
+** A non-static declaration of tzsetwall in a system header file
+** may cause a warning about this upcoming static declaration...
+*/
+static
+#endif /* !defined STD_INSPIRED */
+void
+tzsetwall P((void))
+{
+	_THREAD_PRIVATE_MUTEX_LOCK(lcl);
+	tzsetwall_basic();
+	_THREAD_PRIVATE_MUTEX_UNLOCK(lcl);
+}
+
+static
 void
-tzset P((void))
+tzset_basic P((void))
 {
 	register const char *	name;
 
 	name = getenv("TZ");
 	if (name == NULL) {
-		tzsetwall();
+		tzsetwall_basic();
 		return;
 	}
 
@@ -990,6 +1002,14 @@ tzset P((void))
 	settzname();
 }
 
+void
+tzset P((void))
+{
+	_THREAD_PRIVATE_MUTEX_LOCK(lcl);
+	tzset_basic();
+	_THREAD_PRIVATE_MUTEX_UNLOCK(lcl);
+}
+
 /*
 ** The easy way to behave "as if no library function calls" localtime
 ** is to not call it--so we drop its guts into "localsub", which can be
@@ -1047,12 +1067,27 @@ struct tm * const	tmp;
 }
 
 struct tm *
+localtime_r(timep, p_tm)
+const time_t * const	timep;
+struct tm *p_tm;
+{
+	_THREAD_PRIVATE_MUTEX_LOCK(lcl);
+	tzset_basic();
+	localsub(timep, 0L, p_tm);
+	_THREAD_PRIVATE_MUTEX_UNLOCK(lcl);
+	return p_tm;
+}
+
+struct tm *
 localtime(timep)
 const time_t * const	timep;
 {
-	tzset();
-	localsub(timep, 0L, &tm);
-	return &tm;
+	_THREAD_PRIVATE_KEY(localtime)
+	struct tm * p_tm = (struct tm*)_THREAD_PRIVATE(localtime, tm, NULL);
+
+	if (p_tm == NULL)
+		return NULL;
+	return localtime_r(timep, p_tm);
 }
 
 /*
@@ -1065,6 +1100,7 @@ const time_t * const	timep;
 const long		offset;
 struct tm * const	tmp;
 {
+	_THREAD_PRIVATE_MUTEX_LOCK(gmt);
 	if (!gmt_is_set) {
 		gmt_is_set = TRUE;
 #ifdef ALL_STATE
@@ -1073,6 +1109,7 @@ struct tm * const	tmp;
 #endif /* defined ALL_STATE */
 			gmtload(gmtptr);
 	}
+	_THREAD_PRIVATE_MUTEX_UNLOCK(gmt);
 	timesub(timep, offset, gmtptr, tmp);
 #ifdef TM_ZONE
 	/*
@@ -1096,11 +1133,25 @@ struct tm * const	tmp;
 }
 
 struct tm *
+gmtime_r(timep, p_tm)
+const time_t *		timep;
+struct tm *		p_tm;
+{
+	gmtsub(timep, 0L, p_tm);
+	return p_tm;
+}
+
+struct tm *
 gmtime(timep)
 const time_t * const	timep;
 {
-	gmtsub(timep, 0L, &tm);
-	return &tm;
+	_THREAD_PRIVATE_KEY(gmtime)
+	struct tm * p_tm = (struct tm*) _THREAD_PRIVATE(gmtime, tm, NULL);
+
+	if (p_tm == NULL)
+		return NULL;
+	return gmtime_r(timep, p_tm);
+
 }
 
 #ifdef STD_INSPIRED
@@ -1230,6 +1281,15 @@ const time_t * const	timep;
 	return asctime(localtime(timep));
 }
 
+char *
+ctime_r(timep, buf)
+const time_t * const	timep;
+char * buf;
+{
+	struct tm tm;
+	return asctime_r(localtime_r(timep, &tm), buf);
+}
+
 /*
 ** Adapted from code provided by Robert Elz, who writes:
 **	The "best" way to do mktime I think is based on an idea of Bob
@@ -1534,8 +1594,13 @@ time_t
 mktime(tmp)
 struct tm * const	tmp;
 {
-	tzset();
-	return time1(tmp, localsub, 0L);
+	time_t ret;
+
+	_THREAD_PRIVATE_MUTEX_LOCK(lcl);
+	tzset_basic();
+	ret = time1(tmp, localsub, 0L);
+	_THREAD_PRIVATE_MUTEX_UNLOCK(lcl);
+	return ret;
 }
 
 #ifdef STD_INSPIRED
diff --git a/lib/libc/yp/Makefile.inc b/lib/libc/yp/Makefile.inc
index 8790fca3009..80fdff63f21 100644
--- a/lib/libc/yp/Makefile.inc
+++ b/lib/libc/yp/Makefile.inc
@@ -1,7 +1,7 @@
-#	$OpenBSD: Makefile.inc,v 1.3 1996/07/01 07:08:52 deraadt Exp $
+#	$OpenBSD: Makefile.inc,v 1.4 1998/11/20 11:18:56 d Exp $
 
 # yp sources
-.PATH: ${.CURDIR}/arch/${MACHINE_ARCH}/yp ${.CURDIR}/yp
+.PATH: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/yp ${LIBCSRCDIR}/yp
 
 SRCS+=	ypmatch_cache.c yp_bind.c yp_get_default_domain.c \
 	yp_first.c yp_all.c yp_order.c \
diff --git a/lib/libc_r/Makefile b/lib/libc_r/Makefile
index c7b3ee47d5b..8c75d02a794 100644
--- a/lib/libc_r/Makefile
+++ b/lib/libc_r/Makefile
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile,v 1.2 1998/11/09 03:12:53 d Exp $
+#	$OpenBSD: Makefile,v 1.3 1998/11/20 11:18:57 d Exp $
 #
 # All library objects contain sccsid strings by default; they may be
 # excluded as a space-saving measure.  To produce a library that does
@@ -40,8 +40,10 @@ HIDDEN_SYSCALLS= accept.o bind.o close.o connect.o dup.o dup2.o \
 	signanosleep.o socket.o socketpair.o wait4.o write.o writev.o \
 	_exit.o getlogin.o
 
-.include "${.CURDIR}/../libc/Makefile.inc"
-# let manual pages be built/installed from libc
+LIBCSRCDIR = ${.CURDIR}/../libc
+.include "${LIBCSRCDIR}/Makefile.inc"
+
+# libc man pages built/installed by libc
 MAN=
 MLINKS=
 
diff --git a/lib/libc_r/TODO b/lib/libc_r/TODO
index ab6650e1db3..b643c668900 100644
--- a/lib/libc_r/TODO
+++ b/lib/libc_r/TODO
@@ -1,12 +1,18 @@
 
 This is a list of things that still need to be done:
 
-* Fix the totally bogus _atomic_lock in arch/mips
+* Fix the totally bogus _atomic_lock in arch/mips.
+  This is a nightmare because you really need to incur a ctxt switch
+  for pmaxen. R4000 has some instructions to do an atomic test-and-set
+  but not mips1. fuck fuck fuck. the ctx switch has to be sigsetmask
 
 * Add thread stuff to the other archs in libc/arch/; ie change
   some usages of ENTRY to SYSENTRY in some .S files and add
   the new macros to their SYS.h. Only the i386 arch is working.
 
+* Finish/verify the md stuff for setjmp and atomic_lock for sparc and
+  alpha. Boy do they look dodgy.
+
 * Find a better way of doing the _sys_aliases stuff; ideally by
   using the linker. jmp's (current implementation) are ugly, but
   I don't want to have to hack ../libc/sys/Makefile.inc just to
@@ -17,16 +23,25 @@ This is a list of things that still need to be done:
   instead of libc_r.a ... some kind of shlib common problem? may
   need to use crt0 instead? __CTOR_LIST__ is just not being updated by ld.
   Frankly this one is driving me nuts. Maybe <bsd.lib.mk> is wrong.
-
-* Signals seem to cause busy-hangs. SIGINFO especially. test_sock_2
-  fails because of its use of signals. still dumps /tmp/uthread.dump
-  though - needs debugging.
+  This varies on different architectures and exec format.
 
 * Test the objective-C compiler to see if it can use threads.
+  Really this shows up a nasty problem with needing to say -threads
+  whenever you want to use threads. Ideally, linking with -lc_r library
+  would override -lc; but the _POSIX_THREADS define would alter
+  some optimisations done in <stdio.h>... What to do!?! FreeBSD looks
+  like they are going to have an always-threaded libc with optimisations
+  for the 1-thread case and use weak symbols to override functions when
+  someone uses -lc_r. Do we have weak symbols everywhere? I wonder
+  what the performance hit is if #define LOCK() if(nthreads>1){lock();}
+  is used... need to profile this.
 
 * Find all the static buffers in libc and make them per-thread. This
   is not absolutely necessary but incurs no penalty for single-threaded
   operation, and makes life easier & safer for when threads are used.
+  On the other hand, it adds a bit more code bloat when you use threads
+  and makes openbsd programs non-portable to other OSs with less-nicer
+  libraries. If we do the bare posix minimum, we promote portable code.
   
 * Look into how netbsd are going with their kernel threads
 
@@ -40,4 +55,9 @@ This is a list of things that still need to be done:
   May also need to document "This is not thread-safe" for some library
   functions (yet to be identified).
 
-$OpenBSD: TODO,v 1.2 1998/11/09 03:12:54 d Exp $
+* Find out where freebsd/netbsd use pread() and pwrite().. i think
+  its in the database routines mostly. We will need to rip their code.
+
+* Figure out what to do with the configuration system variables (_SC_*)
+
+$OpenBSD: TODO,v 1.3 1998/11/20 11:18:57 d Exp $
diff --git a/share/man/man3/intro.3 b/share/man/man3/intro.3
index 0da783993ce..538762eec78 100644
--- a/share/man/man3/intro.3
+++ b/share/man/man3/intro.3
@@ -77,6 +77,12 @@ string operators,
 character tests and character operators,
 des encryption routines,
 storage allocation, time functions, signal handling and more.
+.It Xr libc_r Pq Fl l Ns Ar c_r
+Reentrant C library. Contains POSIX 1003.1c
+.Xr pthreads 3
+API, thread scheduler, and thread-safe variants of all functions
+found in
+.Xr libc .
 .It Xo
 .Xr libcurses
 .Pf ( Fl l Ns Ar curses
@@ -149,7 +155,8 @@ the math library compiled for profiling
 .Xr intro 2 ,
 .Xr cc 1 ,
 .Xr ld 1 ,
-.Xr nm 1
+.Xr nm 1 ,
+.Xr pthreads 3
 .\" .Sh LIST OF FUNCTIONS
 .\" .Bl -column "strncasecmpxxx" "system"
 .\" .Sy Name	Description
diff --git a/sys/sys/unistd.h b/sys/sys/unistd.h
index 8cae3c6b84f..c73f2e0af14 100644
--- a/sys/sys/unistd.h
+++ b/sys/sys/unistd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: unistd.h,v 1.7 1998/07/13 00:56:54 millert Exp $	*/
+/*	$OpenBSD: unistd.h,v 1.8 1998/11/20 11:19:01 d Exp $	*/
 /*	$NetBSD: unistd.h,v 1.10 1994/06/29 06:46:06 cgd Exp $	*/
 
 /*
@@ -119,6 +119,24 @@
 #define	_SC_FSYNC		29
 #define	_SC_XOPEN_SHM		30
 
+/* P1003.1c */
+#define _SC_GETGR_R_SIZE_MAX
+#define _SC_GETPW_R_SIZE_MAX
+#define _SC_LOGIN_NAME_MAX
+#define _SC_THREAD_DESTRUCTOR_ITERATIONS
+#define _SC_THREAD_KEYS_MAX
+#define _SC_THREAD_STACK_MIN
+#define _SC_THREAD_THREADS_MAX
+#define _SC_TTY_NAME_MAX
+#define _SC_THREADS
+#define _SC_THREAD_ATTR_STACKADDR
+#define _SC_THREAD_ATTR_STACKSIZE
+#define _SC_THREAD_PRIORITY_SCHEDULING
+#define _SC_THREAD_PRIO_INHERIT
+#define _SC_THREAD_PRIO_PROTECT
+#define _SC_THREAD_PROCESS_SHARED
+#define _SC_THREAD_SAFE_FUNCTIONS
+
 /* configurable system strings */
 #define	_CS_PATH		 1
 
diff --git a/usr.sbin/named/dig/Makefile b/usr.sbin/named/dig/Makefile
index 13307071f27..d26e517282a 100644
--- a/usr.sbin/named/dig/Makefile
+++ b/usr.sbin/named/dig/Makefile
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile,v 1.5 1997/04/13 21:25:34 provos Exp $
+#	$OpenBSD: Makefile,v 1.6 1998/11/20 11:19:01 d Exp $
 #	$NetBSD: Makefile,v 1.2 1996/03/31 13:55:34 mrg Exp $
 # from: $Id: Makefile,v 8.1 1994/12/15 06:23:45 vixie Exp 
 
@@ -10,6 +10,8 @@ PROG=	dig
 SRCS=	dig.c list.c subr.c debug.c send.c base64.c gethostnamadr.c res_comp.c \
 	res_debug.c res_init.c res_mkquery.c res_query.c res_send.c \
 	res_random.c inet_ntop.c inet_pton.c
+INCLUDE+=-I${.CURDIR}/../../../lib/libc/include
+INCLUDE+=-I${.CURDIR}/..
 CFLAGS+=${INCLUDE} ${CONFIG} -DDEBUG
 
 .include <bsd.prog.mk>