1 files changed, 29 insertions, 0 deletions
diff --git a/src/wctype/iswupper.c b/src/wctype/iswupper.c
new file mode 100644
index 00000000..27fe2359
--- /dev/null
+++ b/src/wctype/iswupper.c
@@ -0,0 +1,29 @@
+#include <wctype.h>
+#include "wchar.h"
+#include "nonstd/assert.h"
+
+/** test whether a wide character is an uppercase letter **/
+int iswupper(wint_t wc)
+{
+	ASSERT_REPRESENTABLE(wc, WCHAR_MIN, WCHAR_MAX, "wchar_t", WEOF);
+
+	wctype_t upper = wctype("upper");
+	return iswctype(wc, upper);
+}
+
+/***
+The fn(iswupper) function tests whether arg(wc) is a wide character in the class
+cclass(upper) in the current locale.
+***/
+
+/* RETURN(NZ): arg(wc) is an uppercase letter */
+/* RETURN(0): arg(wc) is not an uppercase letter */
+
+/* UNSPECIFIED: - */
+/* IMPLEMENTATION: - */
+/* LOCALE: LC_CTYPE */
+
+
+/*
+STDC(199409)
+*/