New -find action report_lba

libisoburn/trunk/xorriso/README

@@ -147,6 +147,26 @@ and vice versa:
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+                             File Formats
+
+Currently there is only one file format peculiar to xorriso : sector maps
+which describe the valid and invalid blocks on a media or a disk copy of
+a media. xorriso creates and reads these file with its option -check_media.
+
+The file begins with 32 bytes of cleartext of which the last one is a
+newline character. The first 25 say "xorriso sector bitmap v2 ", the
+remaining six characters give the size of the info text as decimal number.
+This number of bytes follows the first 32 and will not be interpreted
+by xorriso. They are rather to inform a human reader about the media type
+and its track layout.
+After the info text there are two 4 byte signed integers, most significant
+byte first. The first one, N, gives the number of bits in the following bitmap
+and the second number S gives the number of 2 KiB blocks governed by a single
+bit in the map. Then come the bits in form of 8-bit bytes.
+Media block M is covered by bit B=M/S in the map, bit number B is stored in
+byte B/8 as bit B%8. A valid readable data block has its bit set to 1.
+
+
                              libisoburn
 
 xorriso is based on libisofs which does ISO 9600 filesystem aspects and on