The only thing that was translated into multiple languages in OpenBSD

are the errno messages and signal names.  Everything else is in
English.  We are not planning to translate more text.  Running a
mixed system with less than 1% of the text in native language makes
no sense.  So remove the NLS support from libc messages.  The
catopen(3) functions stay as they are.
OK stsp@ mpi@

src/lib/libc/string/strerror_r.c

@@ -1,10 +1,6 @@
-/* $OpenBSD: strerror_r.c,v 1.11 2015/09/06 20:26:20 guenther Exp $ */
+/* $OpenBSD: strerror_r.c,v 1.12 2015/10/25 10:22:09 bluhm Exp $ */
 /* Public Domain <marc@snafu.org> */
 
-#ifdef NLS
-#include <nl_types.h>
-#endif
-
 #include <errno.h>
 #include <limits.h>
 #include <signal.h>
@@ -66,26 +62,12 @@ __num2string(int num, int sign, int setid, char *buf, size_t buflen,
 	int ret = 0;
 	size_t len;
 
-#ifdef NLS
-	nl_catd catd;
-	catd = catopen("libc", NL_CAT_LOCALE);
-#endif
-
 	if (0 <= num && num < max) {
-#ifdef NLS
-		len = strlcpy(buf, catgets(catd, setid, num, list[num]),
-		    buflen);
-#else
 		len = strlcpy(buf, list[num], buflen);
-#endif
 		if (len >= buflen)
 			ret = ERANGE;
 	} else {
-#ifdef NLS
-		len = strlcpy(buf, catgets(catd, setid, 0xffff, def), buflen);
-#else
 		len = strlcpy(buf, def, buflen);
-#endif
 		if (len >= buflen)
 			ret = ERANGE;
 		else {
@@ -95,10 +77,6 @@ __num2string(int num, int sign, int setid, char *buf, size_t buflen,
 		}
 	}
 
-#ifdef NLS
-	catclose(catd);
-#endif
-
 	return ret;
 }