diff -u a/Makefile b/Makefile
--- a/Makefile	2014-11-24 12:33:39.000000000 +0000
+++ b/Makefile	2020-10-11 03:17:17.000000000 +0000
@@ -1,13 +1,13 @@
 .SUFFIXES:
 
 DESTDIR=
-prefix=/usr/local
+prefix=
 bindir=$(prefix)/bin
-mandir=$(prefix)/man
-man1dir=$(mandir)/man1
 sharedir=$(prefix)/share
 getoptdir=$(sharedir)/getopt
 localedir=$(sharedir)/locale
+mandir=$(sharedir)/man
+man1dir=$(mandir)/man1
 
 # Define this to 0 to use the getopt(3) routines in this package.
 LIBCGETOPT=1
diff -u a/getopt.c b/getopt.c
--- a/getopt.c	2020-10-11 03:18:14.030000000 +0000
+++ b/getopt.c	2020-10-11 03:21:20.480000000 +0000
@@ -377,7 +377,9 @@
 		{NULL, 0, NULL, 0}
 	};
 
+	#ifdef LC_ALL
 	setlocale(LC_ALL, "");
+	#endif
 	bindtextdomain(PACKAGE, LOCALEDIR);
 	textdomain(PACKAGE);