cbb2063e__SG_IO_ioctl_in_the_2_6_series_inimum_permission_requirements_Comments
[SCSI command] PLAY CD [(draft) standard] MMC-2 [sg driver requires] O_RDWR O_RDONLY [Comments] 
old, now SPARE IN in SPC-4
Linux SG_IO ioctl in the 2.6 series
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