diff --git a/contrib/tzcode/tzconfig.h b/contrib/tzcode/tzconfig.h
--- a/contrib/tzcode/tzconfig.h
+++ b/contrib/tzcode/tzconfig.h
@@ -13,7 +13,7 @@
 #define NETBSD_INSPIRED	0
 #define STD_INSPIRED	1
 #define HAVE_TZNAME	2
-#define USG_COMPAT	0
+#define USG_COMPAT	2
 #define ALTZONE		0
 
 #endif /* !TZCONFIG_H_INCLUDED */
diff --git a/include/time.h b/include/time.h
--- a/include/time.h
+++ b/include/time.h
@@ -162,10 +162,11 @@
 #if __XSI_VISIBLE
 char *strptime(const char * __restrict, const char * __restrict,
     struct tm * __restrict);
+extern long timezone;
+extern int daylight;
 #endif
 
 #if __BSD_VISIBLE
-char *timezone(int, int);	/* XXX XSI conflict */
 time_t timelocal(struct tm * const);
 time_t timegm(struct tm * const);
 int timer_oshandle_np(timer_t timerid);
diff --git a/lib/libc/gen/Makefile.inc b/lib/libc/gen/Makefile.inc
--- a/lib/libc/gen/Makefile.inc
+++ b/lib/libc/gen/Makefile.inc
@@ -307,7 +307,6 @@
 	times.3 \
 	timespec_get.3 \
 	timespec_getres.3 \
-	timezone.3 \
 	ttyname.3 \
 	tzset.3 \
 	ualarm.3 \
@@ -535,6 +534,8 @@
 	tcsetattr.3 tcgetattr.3
 MLINKS+=ttyname.3 isatty.3 \
 	ttyname.3 ttyname_r.3
+MLINKS+=tzset.3 daylight.3 \
+	tzset.3 timezone.3
 MLINKS+=unvis.3 strunvis.3 \
 	unvis.3 strunvisx.3
 MLINKS+=vis.3 nvis.3 \
diff --git a/lib/libc/gen/Symbol.map b/lib/libc/gen/Symbol.map
--- a/lib/libc/gen/Symbol.map
+++ b/lib/libc/gen/Symbol.map
@@ -261,7 +261,6 @@
 	setlogmask;
 	ttyname_r;
 	ttyname;
-	timezone;
 	times;
 	time;
 	telldir;
diff --git a/lib/libc/gen/timezone.3 b/lib/libc/gen/timezone.3
deleted file mode 100644
--- a/lib/libc/gen/timezone.3
+++ /dev/null
@@ -1,66 +0,0 @@
-.\" Copyright (c) 1991, 1993
-.\"	The Regents of the University of California.  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. Neither the name of the University nor the names of its 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
-.\" 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.
-.\"
-.Dd April 19, 1994
-.Dt TIMEZONE 3
-.Os
-.Sh NAME
-.Nm timezone
-.Nd return the timezone abbreviation
-.Sh LIBRARY
-.Lb libc
-.Sh SYNOPSIS
-.Ft char *
-.Fn timezone "int zone" "int dst"
-.Sh DESCRIPTION
-.Bf Sy
-This interface is for compatibility only; it is impossible to reliably
-map timezone's arguments to a time zone abbreviation.
-See
-.Xr ctime 3 .
-.Ef
-.Pp
-The
-.Fn timezone
-function returns a pointer to a time zone abbreviation for the specified
-.Fa zone
-and
-.Fa dst
-values.
-The
-.Fa zone
-argument
-is the number of minutes west of GMT and
-.Fa dst
-is non-zero if daylight savings time is in effect.
-.Sh SEE ALSO
-.Xr ctime 3
-.Sh HISTORY
-A
-.Fn timezone
-function appeared in
-.At v7 .
diff --git a/lib/libc/gen/timezone.c b/lib/libc/gen/timezone.c
--- a/lib/libc/gen/timezone.c
+++ b/lib/libc/gen/timezone.c
@@ -36,7 +36,7 @@
 #include <string.h>
 #define TZ_MAX_CHARS 255
 
-char *_tztab(int, int);
+static char *_tztab(int, int);
 
 /*
  * timezone --
@@ -49,7 +49,7 @@
 static char	czone[TZ_MAX_CHARS];		/* space for zone name */
 
 char *
-timezone(int zone, int dst)
+__timezone_compat(int zone, int dst)
 {
 	char	*beg,
 			*end;
@@ -68,6 +68,7 @@
 	}
 	return(_tztab(zone,dst));	/* default: table or created zone */
 }
+__sym_compat(timezone, __timezone_compat, FBSD_1.0);
 
 static struct zone {
 	int	offset;
@@ -99,7 +100,7 @@
  *	aren't in place in /etc.  DO NOT USE THIS ROUTINE OUTSIDE OF THE
  *	STANDARD LIBRARY.
  */
-char *
+static char *
 _tztab(int zone, int dst)
 {
 	struct zone	*zp;
diff --git a/lib/libc/gen/tzset.3 b/lib/libc/gen/tzset.3
--- a/lib/libc/gen/tzset.3
+++ b/lib/libc/gen/tzset.3
@@ -28,16 +28,22 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.Dd March 6, 2023
+.Dd December 25, 2023
 .Dt TZSET 3
 .Os
 .Sh NAME
+.Nm daylight ,
+.Nm timezone ,
+.Nm tzname ,
 .Nm tzset
 .Nd initialize time conversion information
 .Sh LIBRARY
 .Lb libc
 .Sh SYNOPSIS
 .In time.h
+.Vt extern int daylight ;
+.Vt extern long timezone ;
+.Vt extern char *tzname[2] ;
 .Ft void
 .Fn tzset void
 .Sh DESCRIPTION
@@ -93,6 +99,21 @@
 file and cannot be interpreted as a direct specification,
 .Tn UTC
 is used.
+.Pp
+After the first call to
+.Nm tzset ,
+the
+.Vt timezone
+variable is set to the difference, in seconds, between Coordinated Universal
+Time (UTC) and the local time.
+The
+.Vt daylight
+variable is set to 0 if the local timezone is observing standard time.
+It is set to 1 if the local timezone ever observes an alternate time, such as summer time.
+The first element of the
+.Vt tzname
+array is the timezone name of standard time, while the second element is the
+name of the altnerative time zone.
 .Sh SPECIFICATION FORMAT
 When
 .Ev TZ
diff --git a/lib/libc/stdtime/Symbol.map b/lib/libc/stdtime/Symbol.map
--- a/lib/libc/stdtime/Symbol.map
+++ b/lib/libc/stdtime/Symbol.map
@@ -30,3 +30,8 @@
 	asctime_r;
 	asctime;
 };
+
+FBSD_1.8 {
+	daylight;
+	timezone;
+};