0001 ============================
0002 Summary of CDROM ioctl calls
0003 ============================
0004
0005 - Edward A. Falk <efalk@google.com>
0006
0007 November, 2004
0008
0009 This document attempts to describe the ioctl(2) calls supported by
0010 the CDROM layer. These are by-and-large implemented (as of Linux 2.6)
0011 in drivers/cdrom/cdrom.c and drivers/block/scsi_ioctl.c
0012
0013 ioctl values are listed in <linux/cdrom.h>. As of this writing, they
0014 are as follows:
0015
0016 ======================== ===============================================
0017 CDROMPAUSE Pause Audio Operation
0018 CDROMRESUME Resume paused Audio Operation
0019 CDROMPLAYMSF Play Audio MSF (struct cdrom_msf)
0020 CDROMPLAYTRKIND Play Audio Track/index (struct cdrom_ti)
0021 CDROMREADTOCHDR Read TOC header (struct cdrom_tochdr)
0022 CDROMREADTOCENTRY Read TOC entry (struct cdrom_tocentry)
0023 CDROMSTOP Stop the cdrom drive
0024 CDROMSTART Start the cdrom drive
0025 CDROMEJECT Ejects the cdrom media
0026 CDROMVOLCTRL Control output volume (struct cdrom_volctrl)
0027 CDROMSUBCHNL Read subchannel data (struct cdrom_subchnl)
0028 CDROMREADMODE2 Read CDROM mode 2 data (2336 Bytes)
0029 (struct cdrom_read)
0030 CDROMREADMODE1 Read CDROM mode 1 data (2048 Bytes)
0031 (struct cdrom_read)
0032 CDROMREADAUDIO (struct cdrom_read_audio)
0033 CDROMEJECT_SW enable(1)/disable(0) auto-ejecting
0034 CDROMMULTISESSION Obtain the start-of-last-session
0035 address of multi session disks
0036 (struct cdrom_multisession)
0037 CDROM_GET_MCN Obtain the "Universal Product Code"
0038 if available (struct cdrom_mcn)
0039 CDROM_GET_UPC Deprecated, use CDROM_GET_MCN instead.
0040 CDROMRESET hard-reset the drive
0041 CDROMVOLREAD Get the drive's volume setting
0042 (struct cdrom_volctrl)
0043 CDROMREADRAW read data in raw mode (2352 Bytes)
0044 (struct cdrom_read)
0045 CDROMREADCOOKED read data in cooked mode
0046 CDROMSEEK seek msf address
0047 CDROMPLAYBLK scsi-cd only, (struct cdrom_blk)
0048 CDROMREADALL read all 2646 bytes
0049 CDROMGETSPINDOWN return 4-bit spindown value
0050 CDROMSETSPINDOWN set 4-bit spindown value
0051 CDROMCLOSETRAY pendant of CDROMEJECT
0052 CDROM_SET_OPTIONS Set behavior options
0053 CDROM_CLEAR_OPTIONS Clear behavior options
0054 CDROM_SELECT_SPEED Set the CD-ROM speed
0055 CDROM_SELECT_DISC Select disc (for juke-boxes)
0056 CDROM_MEDIA_CHANGED Check is media changed
0057 CDROM_TIMED_MEDIA_CHANGE Check if media changed
0058 since given time
0059 (struct cdrom_timed_media_change_info)
0060 CDROM_DRIVE_STATUS Get tray position, etc.
0061 CDROM_DISC_STATUS Get disc type, etc.
0062 CDROM_CHANGER_NSLOTS Get number of slots
0063 CDROM_LOCKDOOR lock or unlock door
0064 CDROM_DEBUG Turn debug messages on/off
0065 CDROM_GET_CAPABILITY get capabilities
0066 CDROMAUDIOBUFSIZ set the audio buffer size
0067 DVD_READ_STRUCT Read structure
0068 DVD_WRITE_STRUCT Write structure
0069 DVD_AUTH Authentication
0070 CDROM_SEND_PACKET send a packet to the drive
0071 CDROM_NEXT_WRITABLE get next writable block
0072 CDROM_LAST_WRITTEN get last block written on disc
0073 ======================== ===============================================
0074
0075
0076 The information that follows was determined from reading kernel source
0077 code. It is likely that some corrections will be made over time.
0078
0079 ------------------------------------------------------------------------------
0080
0081 General:
0082
0083 Unless otherwise specified, all ioctl calls return 0 on success
0084 and -1 with errno set to an appropriate value on error. (Some
0085 ioctls return non-negative data values.)
0086
0087 Unless otherwise specified, all ioctl calls return -1 and set
0088 errno to EFAULT on a failed attempt to copy data to or from user
0089 address space.
0090
0091 Individual drivers may return error codes not listed here.
0092
0093 Unless otherwise specified, all data structures and constants
0094 are defined in <linux/cdrom.h>
0095
0096 ------------------------------------------------------------------------------
0097
0098
0099 CDROMPAUSE
0100 Pause Audio Operation
0101
0102
0103 usage::
0104
0105 ioctl(fd, CDROMPAUSE, 0);
0106
0107
0108 inputs:
0109 none
0110
0111
0112 outputs:
0113 none
0114
0115
0116 error return:
0117 - ENOSYS cd drive not audio-capable.
0118
0119
0120 CDROMRESUME
0121 Resume paused Audio Operation
0122
0123
0124 usage::
0125
0126 ioctl(fd, CDROMRESUME, 0);
0127
0128
0129 inputs:
0130 none
0131
0132
0133 outputs:
0134 none
0135
0136
0137 error return:
0138 - ENOSYS cd drive not audio-capable.
0139
0140
0141 CDROMPLAYMSF
0142 Play Audio MSF
0143
0144 (struct cdrom_msf)
0145
0146
0147 usage::
0148
0149 struct cdrom_msf msf;
0150
0151 ioctl(fd, CDROMPLAYMSF, &msf);
0152
0153 inputs:
0154 cdrom_msf structure, describing a segment of music to play
0155
0156
0157 outputs:
0158 none
0159
0160
0161 error return:
0162 - ENOSYS cd drive not audio-capable.
0163
0164 notes:
0165 - MSF stands for minutes-seconds-frames
0166 - LBA stands for logical block address
0167 - Segment is described as start and end times, where each time
0168 is described as minutes:seconds:frames.
0169 A frame is 1/75 of a second.
0170
0171
0172 CDROMPLAYTRKIND
0173 Play Audio Track/index
0174
0175 (struct cdrom_ti)
0176
0177
0178 usage::
0179
0180 struct cdrom_ti ti;
0181
0182 ioctl(fd, CDROMPLAYTRKIND, &ti);
0183
0184 inputs:
0185 cdrom_ti structure, describing a segment of music to play
0186
0187
0188 outputs:
0189 none
0190
0191
0192 error return:
0193 - ENOSYS cd drive not audio-capable.
0194
0195 notes:
0196 - Segment is described as start and end times, where each time
0197 is described as a track and an index.
0198
0199
0200
0201 CDROMREADTOCHDR
0202 Read TOC header
0203
0204 (struct cdrom_tochdr)
0205
0206
0207 usage::
0208
0209 cdrom_tochdr header;
0210
0211 ioctl(fd, CDROMREADTOCHDR, &header);
0212
0213 inputs:
0214 cdrom_tochdr structure
0215
0216
0217 outputs:
0218 cdrom_tochdr structure
0219
0220
0221 error return:
0222 - ENOSYS cd drive not audio-capable.
0223
0224
0225
0226 CDROMREADTOCENTRY
0227 Read TOC entry
0228
0229 (struct cdrom_tocentry)
0230
0231
0232 usage::
0233
0234 struct cdrom_tocentry entry;
0235
0236 ioctl(fd, CDROMREADTOCENTRY, &entry);
0237
0238 inputs:
0239 cdrom_tocentry structure
0240
0241
0242 outputs:
0243 cdrom_tocentry structure
0244
0245
0246 error return:
0247 - ENOSYS cd drive not audio-capable.
0248 - EINVAL entry.cdte_format not CDROM_MSF or CDROM_LBA
0249 - EINVAL requested track out of bounds
0250 - EIO I/O error reading TOC
0251
0252 notes:
0253 - TOC stands for Table Of Contents
0254 - MSF stands for minutes-seconds-frames
0255 - LBA stands for logical block address
0256
0257
0258
0259 CDROMSTOP
0260 Stop the cdrom drive
0261
0262
0263 usage::
0264
0265 ioctl(fd, CDROMSTOP, 0);
0266
0267
0268 inputs:
0269 none
0270
0271
0272 outputs:
0273 none
0274
0275
0276 error return:
0277 - ENOSYS cd drive not audio-capable.
0278
0279 notes:
0280 - Exact interpretation of this ioctl depends on the device,
0281 but most seem to spin the drive down.
0282
0283
0284 CDROMSTART
0285 Start the cdrom drive
0286
0287
0288 usage::
0289
0290 ioctl(fd, CDROMSTART, 0);
0291
0292
0293 inputs:
0294 none
0295
0296
0297 outputs:
0298 none
0299
0300
0301 error return:
0302 - ENOSYS cd drive not audio-capable.
0303
0304 notes:
0305 - Exact interpretation of this ioctl depends on the device,
0306 but most seem to spin the drive up and/or close the tray.
0307 Other devices ignore the ioctl completely.
0308
0309
0310 CDROMEJECT
0311 - Ejects the cdrom media
0312
0313
0314 usage::
0315
0316 ioctl(fd, CDROMEJECT, 0);
0317
0318
0319 inputs:
0320 none
0321
0322
0323 outputs:
0324 none
0325
0326
0327 error returns:
0328 - ENOSYS cd drive not capable of ejecting
0329 - EBUSY other processes are accessing drive, or door is locked
0330
0331 notes:
0332 - See CDROM_LOCKDOOR, below.
0333
0334
0335
0336
0337 CDROMCLOSETRAY
0338 pendant of CDROMEJECT
0339
0340
0341 usage::
0342
0343 ioctl(fd, CDROMCLOSETRAY, 0);
0344
0345
0346 inputs:
0347 none
0348
0349
0350 outputs:
0351 none
0352
0353
0354 error returns:
0355 - ENOSYS cd drive not capable of closing the tray
0356 - EBUSY other processes are accessing drive, or door is locked
0357
0358 notes:
0359 - See CDROM_LOCKDOOR, below.
0360
0361
0362
0363
0364 CDROMVOLCTRL
0365 Control output volume (struct cdrom_volctrl)
0366
0367
0368 usage::
0369
0370 struct cdrom_volctrl volume;
0371
0372 ioctl(fd, CDROMVOLCTRL, &volume);
0373
0374 inputs:
0375 cdrom_volctrl structure containing volumes for up to 4
0376 channels.
0377
0378 outputs:
0379 none
0380
0381
0382 error return:
0383 - ENOSYS cd drive not audio-capable.
0384
0385
0386
0387 CDROMVOLREAD
0388 Get the drive's volume setting
0389
0390 (struct cdrom_volctrl)
0391
0392
0393 usage::
0394
0395 struct cdrom_volctrl volume;
0396
0397 ioctl(fd, CDROMVOLREAD, &volume);
0398
0399 inputs:
0400 none
0401
0402
0403 outputs:
0404 The current volume settings.
0405
0406
0407 error return:
0408 - ENOSYS cd drive not audio-capable.
0409
0410
0411
0412 CDROMSUBCHNL
0413 Read subchannel data
0414
0415 (struct cdrom_subchnl)
0416
0417
0418 usage::
0419
0420 struct cdrom_subchnl q;
0421
0422 ioctl(fd, CDROMSUBCHNL, &q);
0423
0424 inputs:
0425 cdrom_subchnl structure
0426
0427
0428 outputs:
0429 cdrom_subchnl structure
0430
0431
0432 error return:
0433 - ENOSYS cd drive not audio-capable.
0434 - EINVAL format not CDROM_MSF or CDROM_LBA
0435
0436 notes:
0437 - Format is converted to CDROM_MSF or CDROM_LBA
0438 as per user request on return
0439
0440
0441
0442 CDROMREADRAW
0443 read data in raw mode (2352 Bytes)
0444
0445 (struct cdrom_read)
0446
0447 usage::
0448
0449 union {
0450
0451 struct cdrom_msf msf; /* input */
0452 char buffer[CD_FRAMESIZE_RAW]; /* return */
0453 } arg;
0454 ioctl(fd, CDROMREADRAW, &arg);
0455
0456 inputs:
0457 cdrom_msf structure indicating an address to read.
0458
0459 Only the start values are significant.
0460
0461 outputs:
0462 Data written to address provided by user.
0463
0464
0465 error return:
0466 - EINVAL address less than 0, or msf less than 0:2:0
0467 - ENOMEM out of memory
0468
0469 notes:
0470 - As of 2.6.8.1, comments in <linux/cdrom.h> indicate that this
0471 ioctl accepts a cdrom_read structure, but actual source code
0472 reads a cdrom_msf structure and writes a buffer of data to
0473 the same address.
0474
0475 - MSF values are converted to LBA values via this formula::
0476
0477 lba = (((m * CD_SECS) + s) * CD_FRAMES + f) - CD_MSF_OFFSET;
0478
0479
0480
0481
0482 CDROMREADMODE1
0483 Read CDROM mode 1 data (2048 Bytes)
0484
0485 (struct cdrom_read)
0486
0487 notes:
0488 Identical to CDROMREADRAW except that block size is
0489 CD_FRAMESIZE (2048) bytes
0490
0491
0492
0493 CDROMREADMODE2
0494 Read CDROM mode 2 data (2336 Bytes)
0495
0496 (struct cdrom_read)
0497
0498 notes:
0499 Identical to CDROMREADRAW except that block size is
0500 CD_FRAMESIZE_RAW0 (2336) bytes
0501
0502
0503
0504 CDROMREADAUDIO
0505 (struct cdrom_read_audio)
0506
0507 usage::
0508
0509 struct cdrom_read_audio ra;
0510
0511 ioctl(fd, CDROMREADAUDIO, &ra);
0512
0513 inputs:
0514 cdrom_read_audio structure containing read start
0515 point and length
0516
0517 outputs:
0518 audio data, returned to buffer indicated by ra
0519
0520
0521 error return:
0522 - EINVAL format not CDROM_MSF or CDROM_LBA
0523 - EINVAL nframes not in range [1 75]
0524 - ENXIO drive has no queue (probably means invalid fd)
0525 - ENOMEM out of memory
0526
0527
0528 CDROMEJECT_SW
0529 enable(1)/disable(0) auto-ejecting
0530
0531
0532 usage::
0533
0534 int val;
0535
0536 ioctl(fd, CDROMEJECT_SW, val);
0537
0538 inputs:
0539 Flag specifying auto-eject flag.
0540
0541
0542 outputs:
0543 none
0544
0545
0546 error return:
0547 - ENOSYS Drive is not capable of ejecting.
0548 - EBUSY Door is locked
0549
0550
0551
0552
0553 CDROMMULTISESSION
0554 Obtain the start-of-last-session address of multi session disks
0555
0556 (struct cdrom_multisession)
0557
0558 usage::
0559
0560 struct cdrom_multisession ms_info;
0561
0562 ioctl(fd, CDROMMULTISESSION, &ms_info);
0563
0564 inputs:
0565 cdrom_multisession structure containing desired
0566
0567 format.
0568
0569 outputs:
0570 cdrom_multisession structure is filled with last_session
0571 information.
0572
0573 error return:
0574 - EINVAL format not CDROM_MSF or CDROM_LBA
0575
0576
0577 CDROM_GET_MCN
0578 Obtain the "Universal Product Code"
0579 if available
0580
0581 (struct cdrom_mcn)
0582
0583
0584 usage::
0585
0586 struct cdrom_mcn mcn;
0587
0588 ioctl(fd, CDROM_GET_MCN, &mcn);
0589
0590 inputs:
0591 none
0592
0593
0594 outputs:
0595 Universal Product Code
0596
0597
0598 error return:
0599 - ENOSYS Drive is not capable of reading MCN data.
0600
0601 notes:
0602 - Source code comments state::
0603
0604 The following function is implemented, although very few
0605 audio discs give Universal Product Code information, which
0606 should just be the Medium Catalog Number on the box. Note,
0607 that the way the code is written on the CD is /not/ uniform
0608 across all discs!
0609
0610
0611
0612
0613 CDROM_GET_UPC
0614 CDROM_GET_MCN (deprecated)
0615
0616
0617 Not implemented, as of 2.6.8.1
0618
0619
0620
0621 CDROMRESET
0622 hard-reset the drive
0623
0624
0625 usage::
0626
0627 ioctl(fd, CDROMRESET, 0);
0628
0629
0630 inputs:
0631 none
0632
0633
0634 outputs:
0635 none
0636
0637
0638 error return:
0639 - EACCES Access denied: requires CAP_SYS_ADMIN
0640 - ENOSYS Drive is not capable of resetting.
0641
0642
0643
0644
0645 CDROMREADCOOKED
0646 read data in cooked mode
0647
0648
0649 usage::
0650
0651 u8 buffer[CD_FRAMESIZE]
0652
0653 ioctl(fd, CDROMREADCOOKED, buffer);
0654
0655 inputs:
0656 none
0657
0658
0659 outputs:
0660 2048 bytes of data, "cooked" mode.
0661
0662
0663 notes:
0664 Not implemented on all drives.
0665
0666
0667
0668
0669
0670 CDROMREADALL
0671 read all 2646 bytes
0672
0673
0674 Same as CDROMREADCOOKED, but reads 2646 bytes.
0675
0676
0677
0678 CDROMSEEK
0679 seek msf address
0680
0681
0682 usage::
0683
0684 struct cdrom_msf msf;
0685
0686 ioctl(fd, CDROMSEEK, &msf);
0687
0688 inputs:
0689 MSF address to seek to.
0690
0691
0692 outputs:
0693 none
0694
0695
0696
0697
0698 CDROMPLAYBLK
0699 scsi-cd only
0700
0701 (struct cdrom_blk)
0702
0703
0704 usage::
0705
0706 struct cdrom_blk blk;
0707
0708 ioctl(fd, CDROMPLAYBLK, &blk);
0709
0710 inputs:
0711 Region to play
0712
0713
0714 outputs:
0715 none
0716
0717
0718
0719
0720 CDROMGETSPINDOWN
0721 Obsolete, was ide-cd only
0722
0723
0724 usage::
0725
0726 char spindown;
0727
0728 ioctl(fd, CDROMGETSPINDOWN, &spindown);
0729
0730 inputs:
0731 none
0732
0733
0734 outputs:
0735 The value of the current 4-bit spindown value.
0736
0737
0738
0739
0740
0741 CDROMSETSPINDOWN
0742 Obsolete, was ide-cd only
0743
0744
0745 usage::
0746
0747 char spindown
0748
0749 ioctl(fd, CDROMSETSPINDOWN, &spindown);
0750
0751 inputs:
0752 4-bit value used to control spindown (TODO: more detail here)
0753
0754
0755 outputs:
0756 none
0757
0758
0759
0760
0761
0762
0763 CDROM_SET_OPTIONS
0764 Set behavior options
0765
0766
0767 usage::
0768
0769 int options;
0770
0771 ioctl(fd, CDROM_SET_OPTIONS, options);
0772
0773 inputs:
0774 New values for drive options. The logical 'or' of:
0775
0776 ============== ==================================
0777 CDO_AUTO_CLOSE close tray on first open(2)
0778 CDO_AUTO_EJECT open tray on last release
0779 CDO_USE_FFLAGS use O_NONBLOCK information on open
0780 CDO_LOCK lock tray on open files
0781 CDO_CHECK_TYPE check type on open for data
0782 ============== ==================================
0783
0784 outputs:
0785 Returns the resulting options settings in the
0786 ioctl return value. Returns -1 on error.
0787
0788 error return:
0789 - ENOSYS selected option(s) not supported by drive.
0790
0791
0792
0793
0794 CDROM_CLEAR_OPTIONS
0795 Clear behavior options
0796
0797
0798 Same as CDROM_SET_OPTIONS, except that selected options are
0799 turned off.
0800
0801
0802
0803 CDROM_SELECT_SPEED
0804 Set the CD-ROM speed
0805
0806
0807 usage::
0808
0809 int speed;
0810
0811 ioctl(fd, CDROM_SELECT_SPEED, speed);
0812
0813 inputs:
0814 New drive speed.
0815
0816
0817 outputs:
0818 none
0819
0820
0821 error return:
0822 - ENOSYS speed selection not supported by drive.
0823
0824
0825
0826 CDROM_SELECT_DISC
0827 Select disc (for juke-boxes)
0828
0829
0830 usage::
0831
0832 int disk;
0833
0834 ioctl(fd, CDROM_SELECT_DISC, disk);
0835
0836 inputs:
0837 Disk to load into drive.
0838
0839
0840 outputs:
0841 none
0842
0843
0844 error return:
0845 - EINVAL Disk number beyond capacity of drive
0846
0847
0848
0849 CDROM_MEDIA_CHANGED
0850 Check is media changed
0851
0852
0853 usage::
0854
0855 int slot;
0856
0857 ioctl(fd, CDROM_MEDIA_CHANGED, slot);
0858
0859 inputs:
0860 Slot number to be tested, always zero except for jukeboxes.
0861
0862 May also be special values CDSL_NONE or CDSL_CURRENT
0863
0864 outputs:
0865 Ioctl return value is 0 or 1 depending on whether the media
0866
0867 has been changed, or -1 on error.
0868
0869 error returns:
0870 - ENOSYS Drive can't detect media change
0871 - EINVAL Slot number beyond capacity of drive
0872 - ENOMEM Out of memory
0873
0874
0875
0876 CDROM_DRIVE_STATUS
0877 Get tray position, etc.
0878
0879
0880 usage::
0881
0882 int slot;
0883
0884 ioctl(fd, CDROM_DRIVE_STATUS, slot);
0885
0886 inputs:
0887 Slot number to be tested, always zero except for jukeboxes.
0888
0889 May also be special values CDSL_NONE or CDSL_CURRENT
0890
0891 outputs:
0892 Ioctl return value will be one of the following values
0893
0894 from <linux/cdrom.h>:
0895
0896 =================== ==========================
0897 CDS_NO_INFO Information not available.
0898 CDS_NO_DISC
0899 CDS_TRAY_OPEN
0900 CDS_DRIVE_NOT_READY
0901 CDS_DISC_OK
0902 -1 error
0903 =================== ==========================
0904
0905 error returns:
0906 - ENOSYS Drive can't detect drive status
0907 - EINVAL Slot number beyond capacity of drive
0908 - ENOMEM Out of memory
0909
0910
0911
0912
0913 CDROM_DISC_STATUS
0914 Get disc type, etc.
0915
0916
0917 usage::
0918
0919 ioctl(fd, CDROM_DISC_STATUS, 0);
0920
0921
0922 inputs:
0923 none
0924
0925
0926 outputs:
0927 Ioctl return value will be one of the following values
0928
0929 from <linux/cdrom.h>:
0930
0931 - CDS_NO_INFO
0932 - CDS_AUDIO
0933 - CDS_MIXED
0934 - CDS_XA_2_2
0935 - CDS_XA_2_1
0936 - CDS_DATA_1
0937
0938 error returns:
0939 none at present
0940
0941 notes:
0942 - Source code comments state::
0943
0944
0945 Ok, this is where problems start. The current interface for
0946 the CDROM_DISC_STATUS ioctl is flawed. It makes the false
0947 assumption that CDs are all CDS_DATA_1 or all CDS_AUDIO, etc.
0948 Unfortunately, while this is often the case, it is also
0949 very common for CDs to have some tracks with data, and some
0950 tracks with audio. Just because I feel like it, I declare
0951 the following to be the best way to cope. If the CD has
0952 ANY data tracks on it, it will be returned as a data CD.
0953 If it has any XA tracks, I will return it as that. Now I
0954 could simplify this interface by combining these returns with
0955 the above, but this more clearly demonstrates the problem
0956 with the current interface. Too bad this wasn't designed
0957 to use bitmasks... -Erik
0958
0959 Well, now we have the option CDS_MIXED: a mixed-type CD.
0960 User level programmers might feel the ioctl is not very
0961 useful.
0962 ---david
0963
0964
0965
0966
0967 CDROM_CHANGER_NSLOTS
0968 Get number of slots
0969
0970
0971 usage::
0972
0973 ioctl(fd, CDROM_CHANGER_NSLOTS, 0);
0974
0975
0976 inputs:
0977 none
0978
0979
0980 outputs:
0981 The ioctl return value will be the number of slots in a
0982 CD changer. Typically 1 for non-multi-disk devices.
0983
0984 error returns:
0985 none
0986
0987
0988
0989 CDROM_LOCKDOOR
0990 lock or unlock door
0991
0992
0993 usage::
0994
0995 int lock;
0996
0997 ioctl(fd, CDROM_LOCKDOOR, lock);
0998
0999 inputs:
1000 Door lock flag, 1=lock, 0=unlock
1001
1002
1003 outputs:
1004 none
1005
1006
1007 error returns:
1008 - EDRIVE_CANT_DO_THIS
1009
1010 Door lock function not supported.
1011 - EBUSY
1012
1013 Attempt to unlock when multiple users
1014 have the drive open and not CAP_SYS_ADMIN
1015
1016 notes:
1017 As of 2.6.8.1, the lock flag is a global lock, meaning that
1018 all CD drives will be locked or unlocked together. This is
1019 probably a bug.
1020
1021 The EDRIVE_CANT_DO_THIS value is defined in <linux/cdrom.h>
1022 and is currently (2.6.8.1) the same as EOPNOTSUPP
1023
1024
1025
1026 CDROM_DEBUG
1027 Turn debug messages on/off
1028
1029
1030 usage::
1031
1032 int debug;
1033
1034 ioctl(fd, CDROM_DEBUG, debug);
1035
1036 inputs:
1037 Cdrom debug flag, 0=disable, 1=enable
1038
1039
1040 outputs:
1041 The ioctl return value will be the new debug flag.
1042
1043
1044 error return:
1045 - EACCES Access denied: requires CAP_SYS_ADMIN
1046
1047
1048
1049 CDROM_GET_CAPABILITY
1050 get capabilities
1051
1052
1053 usage::
1054
1055 ioctl(fd, CDROM_GET_CAPABILITY, 0);
1056
1057
1058 inputs:
1059 none
1060
1061
1062 outputs:
1063 The ioctl return value is the current device capability
1064 flags. See CDC_CLOSE_TRAY, CDC_OPEN_TRAY, etc.
1065
1066
1067
1068 CDROMAUDIOBUFSIZ
1069 set the audio buffer size
1070
1071
1072 usage::
1073
1074 int arg;
1075
1076 ioctl(fd, CDROMAUDIOBUFSIZ, val);
1077
1078 inputs:
1079 New audio buffer size
1080
1081
1082 outputs:
1083 The ioctl return value is the new audio buffer size, or -1
1084 on error.
1085
1086 error return:
1087 - ENOSYS Not supported by this driver.
1088
1089 notes:
1090 Not supported by all drivers.
1091
1092
1093
1094
1095 DVD_READ_STRUCT Read structure
1096
1097 usage::
1098
1099 dvd_struct s;
1100
1101 ioctl(fd, DVD_READ_STRUCT, &s);
1102
1103 inputs:
1104 dvd_struct structure, containing:
1105
1106 =================== ==========================================
1107 type specifies the information desired, one of
1108 DVD_STRUCT_PHYSICAL, DVD_STRUCT_COPYRIGHT,
1109 DVD_STRUCT_DISCKEY, DVD_STRUCT_BCA,
1110 DVD_STRUCT_MANUFACT
1111 physical.layer_num desired layer, indexed from 0
1112 copyright.layer_num desired layer, indexed from 0
1113 disckey.agid
1114 =================== ==========================================
1115
1116 outputs:
1117 dvd_struct structure, containing:
1118
1119 =================== ================================
1120 physical for type == DVD_STRUCT_PHYSICAL
1121 copyright for type == DVD_STRUCT_COPYRIGHT
1122 disckey.value for type == DVD_STRUCT_DISCKEY
1123 bca.{len,value} for type == DVD_STRUCT_BCA
1124 manufact.{len,valu} for type == DVD_STRUCT_MANUFACT
1125 =================== ================================
1126
1127 error returns:
1128 - EINVAL physical.layer_num exceeds number of layers
1129 - EIO Received invalid response from drive
1130
1131
1132
1133 DVD_WRITE_STRUCT Write structure
1134
1135 Not implemented, as of 2.6.8.1
1136
1137
1138
1139 DVD_AUTH Authentication
1140
1141 usage::
1142
1143 dvd_authinfo ai;
1144
1145 ioctl(fd, DVD_AUTH, &ai);
1146
1147 inputs:
1148 dvd_authinfo structure. See <linux/cdrom.h>
1149
1150
1151 outputs:
1152 dvd_authinfo structure.
1153
1154
1155 error return:
1156 - ENOTTY ai.type not recognized.
1157
1158
1159
1160 CDROM_SEND_PACKET
1161 send a packet to the drive
1162
1163
1164 usage::
1165
1166 struct cdrom_generic_command cgc;
1167
1168 ioctl(fd, CDROM_SEND_PACKET, &cgc);
1169
1170 inputs:
1171 cdrom_generic_command structure containing the packet to send.
1172
1173
1174 outputs:
1175 none
1176
1177 cdrom_generic_command structure containing results.
1178
1179 error return:
1180 - EIO
1181
1182 command failed.
1183 - EPERM
1184
1185 Operation not permitted, either because a
1186 write command was attempted on a drive which
1187 is opened read-only, or because the command
1188 requires CAP_SYS_RAWIO
1189 - EINVAL
1190
1191 cgc.data_direction not set
1192
1193
1194
1195 CDROM_NEXT_WRITABLE
1196 get next writable block
1197
1198
1199 usage::
1200
1201 long next;
1202
1203 ioctl(fd, CDROM_NEXT_WRITABLE, &next);
1204
1205 inputs:
1206 none
1207
1208
1209 outputs:
1210 The next writable block.
1211
1212
1213 notes:
1214 If the device does not support this ioctl directly, the
1215
1216 ioctl will return CDROM_LAST_WRITTEN + 7.
1217
1218
1219
1220 CDROM_LAST_WRITTEN
1221 get last block written on disc
1222
1223
1224 usage::
1225
1226 long last;
1227
1228 ioctl(fd, CDROM_LAST_WRITTEN, &last);
1229
1230 inputs:
1231 none
1232
1233
1234 outputs:
1235 The last block written on disc
1236
1237
1238 notes:
1239 If the device does not support this ioctl directly, the
1240 result is derived from the disc's table of contents. If the
1241 table of contents can't be read, this ioctl returns an
1242 error.
