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>B.5. sg changes</H1
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>&#13;The main change is the addition of a new interface structure called
"sg_io_hdr". The existing interface structure (called "sg_header") was found
to be inflexible requiring the concatenation of raw data together with
meta-data in the read() and write() commands.
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>&#13;sg_io_hdr {new interface structure}
SG_IO {new ioctl}
direct IO {present but commented out, see ALLOW_DIO}
procfs output {new information in /proc/scsi/sg directory}
boot/module parameters {new}
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>&#13;Up to 64 bytes of sense data can be obtained from the sg_io_hdr interface
structure. Also a residual count associated with the data transfer is
available (if the lower level driver supports it, if not the residual count
will be 0).
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