+ *
+ * A block device is a device which can only be read/written
+ * with data blocks of constant size: flash memories,
+ * SD cards, hard disks, etc...
+ * This interface is designed to adapt to most block devices and
+ * use peculiar features in order to save CPU time and memory space.
+ *
+ * There is no init function because you do not have to use this
+ * structure directly, specific implementations will supply their own init
+ * functions.
+ *
+ * Error handling is done in a way similar to standard C library: whenever a
+ * function (eg. kblock_flush()) returns error, you need to check the error
+ * code, which is implementation specific.
+ *
+ * Example of code flow:
+ * \code
+ * // init a KBlock-derived class
+ * Flash fls;
+ * flash_init(&fls.blk, 0);
+ *
+ * // use kblock_* functions to access the derived class
+ * kblock_write(&fls.blk, ...);
+ * if (kblock_flush(&fls.blk) == EOF)
+ * {
+ * // oops, error occurred!
+ * int err = kblock_error(&fls.blk);
+ * // handle Flash specific error conditions
+ * // ...
+ * // clear error condition
+ * kblock_clearerr(&fls.blk);
+ * }
+ * \endcode
+ *
+ * \note The KBlock interface is optimized for block reads. If you need a
+ * file-like access, you can use \ref kfile_block.
+ *
+ * \author Francesco Sacchi <batt@develer.com>
+ *
+ * $WIZ$ module_name = "kblock"