cs: initialize locale on startup

The `current-locale` parameer value is transferred to the C lbrary via
`setlocale` on demand by Racket functions that depend on the locale,
but some libraries (like libedit) can also depend on the locale
setting. By default, the C library starts with the "C" locale, so it's
worthwhile to install the default locale on startup, even if that's
not a complete solution to support changes to `current-locale`.

racket/src/io/locale/parameter.rkt

@@ -34,6 +34,8 @@
     (set! installed-locale (current-locale))
     (rktio_set_locale rktio (string->bytes/utf-8 installed-locale))))
 
+(void (sync-locale!))
+
 (define (locale-encoding-is-utf-8?)
   (define t (system-type))
   (define loc (current-locale))

racket/src/io/main.rkt

@@ -33,6 +33,8 @@
                   shared-ltps-place-init!)
          (only-in "locale/cache.rkt"
                   convert-cache-init!)
+         (only-in "locale/parameter.rkt"
+                  sync-locale!)
          "port/place.rkt")
 
 (provide (all-from-out "port/main.rkt")
@@ -69,7 +71,8 @@
   (shared-ltps-place-init!)
   (install-error-value->string-handler!)
   (init-current-directory!)
-  (init-current-ports! in-fd out-fd err-fd cust plumber))
+  (init-current-ports! in-fd out-fd err-fd cust plumber)
+  (sync-locale!))
 
 (define (io-place-destroy!)
   ;; We expect everything based on rktio to be destroyed at this point