TD_READ64

read sectors of data from a disk.

This command reads data from the drive to a supplied buffer.

io_Device

preset by the call to OpenDevice()

io_Unit

preset by the call to OpenDevice()

io_Command

CMD_READ

io_Flags

0 or IOF_QUICK

io_Data

pointer to the buffer where the data should be put

io_Length

number of bytes to read, must be a multiple of the drive block size.

io_Offset

low 32 bit of the byte offset from the start of the disk describing where to read data from, must be a multiple of the drive block size.

io_Actual

high 32 bit of the byte offset where to read data from.

io_Error

0 for success, or an error code as defined in <devices/trackdisk.h>

Some incarnations of the scsi.device, namely those that handle actually IDE devices, were unable to read more than 255 blocks in one go. This bug has been fixed in V47.

TD_WRITE64, TD_WRITE64