diff --git a/include/Makefile b/include/Makefile
index 4c2459a46db3..bd1e28448f1e 100644
--- a/include/Makefile
+++ b/include/Makefile
@@ -17,8 +17,8 @@ FILES=	a.out.h ar.h assert.h bitstring.h ctype.h db.h dirent.h disktab.h \
 	paths.h pthread.h pthread_np.h pwd.h \
 	ranlib.h regex.h regexp.h resolv.h rune.h runetype.h \
 	search.h setjmp.h sgtty.h \
-	signal.h stab.h stddef.h stdio.h stdlib.h string.h stringlist.h \
-	strings.h struct.h sysexits.h tar.h time.h timers.h \
+	signal.h stab.h stdbool.h stddef.h stdio.h stdlib.h string.h \
+	stringlist.h strings.h struct.h sysexits.h tar.h time.h timers.h \
 	ttyent.h unistd.h utime.h utmp.h vis.h
 .if defined(WANT_CSRG_LIBM)
 FILES+=	math.h
diff --git a/include/stdbool.h b/include/stdbool.h
new file mode 100644
index 000000000000..5317aea44e92
--- /dev/null
+++ b/include/stdbool.h
@@ -0,0 +1,54 @@
+/*
+ * Copyright (c) 2000 Jeroen Ruigrok van der Werven <asmodai@FreeBSD.org>
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ *
+ * $FreeBSD$
+ */
+
+/* This should be compliant with the ANSI C99 definition */
+
+#ifndef	_STDBOOL_H_
+#define	_STDBOOL_H_	
+
+/* `_Bool' type must promote to `int' or `unsigned int' */
+typedef enum {
+	false = 0,
+	true = 1
+} _Bool;
+
+/* And those constants must also be available as macros */
+#define	false	false
+#define	true	true
+
+/* User visible type `bool' is provided as a macro which may be redefined */
+#define bool _Bool
+
+/* Inform that everything is fine */
+#define __bool_true_false_are_defined 1
+
+#if __STDC_VERSION__ < 199901L
+typedef int	_Bool;		/* not built into pre-C99 compilers */
+#endif
+
+#endif /* _STDBOOL_H_ */