+/*
+ * FALLOC_FL_INSERT_RANGE is use to insert space within the file size without
+ * overwriting any existing data. The contents of the file beyond offset are
+ * shifted towards right by len bytes to create a hole. As such, this
+ * operation will increase the size of the file by len bytes.
+ *
+ * Different filesystems may implement different limitations on the granularity
+ * of the operation. Most will limit operations to filesystem block size
+ * boundaries, but this boundary may be larger or smaller depending on
+ * the filesystem and/or the configuration of the filesystem or file.
+ *
+ * Attempting to insert space using this flag at OR beyond the end of
+ * the file is considered an illegal operation - just use ftruncate(2) or
+ * fallocate(2) with mode 0 for such type of operations.
+ */
+#define FALLOC_FL_INSERT_RANGE 0x20
+