diff --git a/include/stdio.h b/include/stdio.h
index bbeb2a271ec..f16f6447147 100644
--- a/include/stdio.h
+++ b/include/stdio.h
@@ -432,10 +432,10 @@ FILE	*funopen(const void *,
 #define	fropen(cookie, fn) funopen(cookie, fn, 0, 0, 0)
 #define	fwopen(cookie, fn) funopen(cookie, 0, fn, 0, 0)
 
-typedef ssize_t (cookie_read_function_t)(void *, char *, size_t);
-typedef ssize_t (cookie_write_function_t)(void *, const char *, size_t);
-typedef int (cookie_seek_function_t)(void *, off64_t *, int);
-typedef int (cookie_close_function_t)(void *);
+typedef __ssize_t cookie_read_function_t(void *, char *, size_t);
+typedef __ssize_t cookie_write_function_t(void *, const char *, size_t);
+typedef int cookie_seek_function_t(void *, off64_t *, int);
+typedef int cookie_close_function_t(void *);
 typedef struct {
 	cookie_read_function_t	*read;
 	cookie_write_function_t	*write;