3 cdfs, cddb \- optical disc (CD, DVD, BD) track reader and writer file system
14 .B "grep aux/cddb /mnt/cd/ctl | rc
30 serves a one and a half level directory
35 that provides access to the tracks
36 on discs placed in the disc reader or writer
43 Any MMC-compliant compact disc (CD), DVD,
44 or Blu-ray disc (BD) drive should work.
45 On DVDs and BDs, access to data tracks only is implemented.
47 The top level directory contains one file
63 If the device can write discs
64 and contains a writable disc, the top-level
65 directory also contains an empty directory
70 Files created in these directories
71 appear in the top-level directory
72 as new data or audio tracks, respectively, regardless of name.
74 At any time, any number of tracks
75 may be open for reading or a single track
76 may be open for writing.
77 Writing a disc track is a quasi-real-time operation:
78 the disc writer should be kept saturated with
79 new data to avoid buffer underruns,
80 but modern drives will be told to cope with underruns transparently.
81 To ensure saturation, copying from a file system
82 stored on local disk or memory is recommended.
84 To fixate a disc (close a recordable disc by writing
85 its permanent table of contents), simply
91 The directory removed selects whether
92 the disc is fixated as an audio or data disc;
93 since each track carries its own type information,
94 very few readers care which fixation type was used.
95 Rewritable discs do not require fixation.
97 The top level directory
100 file, into which control messages
102 The current control messages are:
106 Format the rewritable disc (\c
114 Blank the entire rewritable disc in the drive.
117 Blank only the table of contents on the rewritable
121 .\" Close any open tracks on the current disc but do not finalize (fixate) the disc.
124 Eject the disc in the drive.
127 Ingest a disc into the drive.
130 Set the reading and writing speed to use,
131 in units of 1,000-bytes-per-second.
134 requests the optimal speed for the current drive and disc.
144 Drives may round down the speed to one they support.
145 To set reading and writing speeds separately,
146 prefix the speeds with
160 Note that most drives reset the reading and writing speed
161 each time a new disc is inserted.
166 file yields information about the drive.
167 If the drive contains an audio CD, the first line
170 command that can be run to query
171 an internet CD database
172 to get a table of contents.
173 Subsequent lines contain the current and maximum
174 reading and writing speeds.
175 Additional lines may further describe the current disc.
178 takes 4 optional arguments.
185 for the query instead of
186 .LR freedb.freedb.org .
189 option causes the raw database response from the server to be dumped
193 option causes the time of each track to be appended to the normal output.
197 but prints a final line with the total time.
199 Backup to a BD-R disc:
206 tar cf /mnt/cd/wd/x /n/boot
211 Copy the audio tracks from a CD:
216 cp /mnt/cd/a* /tmp/songs
219 Copy the tracks onto a blank CD inserted in the drive,
220 and then fixate the disk as an audio CD.
223 cp /tmp/songs/* /mnt/cd/wa
235 .TF "\fLhttp://www.t10.org\fP"
237 .B http://www.t10.org
238 optical disc interface standards
241 Fixating a BD-R disc records only the first track in the disc's TOC.
242 Any other tracks are still there and their data accessible via
244 There's no need to fixate data discs, except to prevent adding new tracks.
246 Closing a just-written DVD-R track can take minutes
247 while the drive burns the unused part of the track reservation
248 (for the whole disc).
249 Thus only a single DVD-R track can be written on a DVD-R disc;
250 use other media if you need more than one track per disc.
252 There are too many combinations of optical media, each with unique quirks,
254 the cross-product of these tuples:
256 (single-layer dual-layer),
259 Only MMC-compliant disc readers and writers
260 are supported, but it would be easy to add
261 support for early CD writers if desired.