1 files changed, 29 insertions, 0 deletions
diff --git a/src/stdio/vsprintf_s.c b/src/stdio/vsprintf_s.c
new file mode 100644
index 00000000..98a7794f
--- /dev/null
+++ b/src/stdio/vsprintf_s.c
@@ -0,0 +1,29 @@
+#include "stdio.h"
+#include <stdarg.h>
+#include <stdint.h>
+
+/** write formatted output to a string **/
+int vsprintf_s(char *s, rsize_t n, const char *format, va_list arg)
+{
+	__C_EXT(1, 201112L);
+	return vsnprintf(s, SIZE_MAX, format, arg);
+}
+
+/***
+The fn(vsprintf) function is equivalent to fn(sprintf), but with a type(va_list)
+argument instead of variadic arguments. The argument arg(arg) must be
+initialized with fnmacro(va_start) prior to calling fn(vsprintf). The
+fn(vsprintf) function does not call fnmacro(va_end), so the calling function is
+responsible for this.
+***/
+
+/* UNSPECIFIED: ??? */
+/* UNDEFINED: ??? */
+/* IMPLEMENTATION: ??? */
+/* LOCALE: ??? */
+
+/* RETURN: the number of characters written, not including the final char(\0) */
+
+/*
+CEXT1(201112)
+*/