io: directory: implement temporary directories and delete-on-close

io/sys/darwin/misc.h

@@ -0,0 +1,8 @@
+#ifndef _IO_DARWIN_MISC_H_
+#define _IO_DARWIN_MISC_H_
+
+#include <stddef.h>
+
+extern void z__b_io_generate_tmp_filename(char *out, size_t len);
+
+#endif