Add process state

src/fs.c

@@ -13,6 +13,10 @@ fs_node_t *fs_open_at(const fs_node_t *directory, uint64_t index) {
   return fat16_open_at(directory, index);
 }
 
+fs_node_t *fs_open_again(const fs_node_t *source) {
+  return fat16_open_again(source);
+}
+
 void fs_read(const fs_node_t *file, uint64_t offset, uint64_t size, void *to) {
   fat16_read(file, offset, size, to);
 }