diff --git a/bin/ps/extern.h b/bin/ps/extern.h
index 55796699d435..dedac7ee5921 100644
--- a/bin/ps/extern.h
+++ b/bin/ps/extern.h
@@ -41,7 +41,7 @@ struct varent;
 
 extern fixpt_t ccpu;
 extern int eval, fscale, mempages, nlistread, rawcpu, cflag;
-extern int sumrusage, termwidth, totwidth, use_ampm;
+extern int sumrusage, termwidth, totwidth;
 extern VAR var[];
 extern VARENT *vhead;
 
diff --git a/bin/ps/print.c b/bin/ps/print.c
index 37d03a382821..f73c3f06d09b 100644
--- a/bin/ps/print.c
+++ b/bin/ps/print.c
@@ -51,6 +51,7 @@ static const char rcsid[] =
 #include <vm/vm.h>
 
 #include <err.h>
+#include <langinfo.h>
 #include <locale.h>
 #include <math.h>
 #include <nlist.h>
@@ -354,6 +355,7 @@ started(k, ve)
 	time_t then;
 	struct tm *tp;
 	char buf[100];
+	static int  use_ampm = -1;
 
 	v = ve->var;
 	if (!k->ki_valid) {
@@ -361,6 +363,9 @@ started(k, ve)
 		return;
 	}
 
+	if (use_ampm < 0)
+		use_ampm = (*nl_langinfo(T_FMT_AMPM) != '\0');
+
 	then = k->ki_p->ki_start.tv_sec;
 	tp = localtime(&then);
 	if (!now)
diff --git a/bin/ps/ps.c b/bin/ps/ps.c
index 7d5aaeebbd4a..55fdc0782621 100644
--- a/bin/ps/ps.c
+++ b/bin/ps/ps.c
@@ -58,7 +58,6 @@ static const char rcsid[] =
 #include <errno.h>
 #include <fcntl.h>
 #include <kvm.h>
-#include <langinfo.h>
 #include <limits.h>
 #include <locale.h>
 #include <nlist.h>
@@ -83,7 +82,6 @@ int	rawcpu;			/* -C */
 int	sumrusage;		/* -S */
 int	termwidth;		/* width of screen (0 == infinity) */
 int	totwidth;		/* calculated width of requested variables */
-int	use_ampm;		/* use AM/PM time */
 
 static int needuser, needcomm, needenv;
 #if defined(LAZY_PS)
@@ -131,7 +129,6 @@ main(argc, argv)
 	char *nlistf, *memf, *swapf, errbuf[_POSIX2_LINE_MAX];
 
 	(void) setlocale(LC_ALL, "");
-	use_ampm = (*nl_langinfo(T_FMT_AMPM) != '\0');
 
 	if ((ioctl(STDOUT_FILENO, TIOCGWINSZ, (char *)&ws) == -1 &&
 	     ioctl(STDERR_FILENO, TIOCGWINSZ, (char *)&ws) == -1 &&