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+nvme-compare(1)
+===============
+
+NAME
+----
+nvme-compare - Send an NVMe Compare command, provide results
+
+SYNOPSIS
+--------
+[verse]
+'nvme-compare' <device> [--start-block=<slba> | -s <slba>]
+			[--block-count=<nlb> | -c <nlb>]
+			[--data-size=<size> | -z <size>]
+			[--metadata-size=<metasize> | -y <metasize>]
+			[--ref-tag=<reftag> | -r <reftag>]
+			[--data=<data-file> | -d <data-file>]
+			[--metadata=<meta> | -M <meta>]
+			[--prinfo=<prinfo> | -p <prinfo>]
+			[--app-tag-mask=<appmask> | -m <appmask>]
+			[--app-tag=<apptag> | -a <apptag>]
+			[--limited-retry | -l]
+			[--force-unit-access | -f]
+			[--dir-type=<type> | -T <type>]
+			[--dir-spec=<spec> | -S <spec>]
+			[--dsm=<dsm> | -D <dsm>]
+			[--show-command | -v]
+			[--dry-run | -w]
+			[--latency | -t]
+
+DESCRIPTION
+-----------
+The Compare command reads the logical blocks specified by the command
+from the medium and compares the data read to a comparison data buffer
+transferred as part of the command. If the data read from the controller
+and the comparison data buffer are equivalent with no miscompares,
+then the command completes successfully. If there is any miscompare,
+the command completes with an error of Compare Failure. If metadata is
+provided, then a comparison is also performed for the metadata.
+
+OPTIONS
+-------
+-s <slba>::
+--start-block=<slba>::
+	64-bit address of the first block to access.
+
+-c <nlb>::
+--block-count=<nlb>::
+	Number of blocks to be accessed (zero-based).
+
+-z <size>::
+--data-size=<size>::
+	Size of data to be compared in bytes.
+
+-y <metasize>::
+--metadata-size=<metasize>::
+	Size of metadata to be trasnferred in bytes.
+
+-r <reftag>::
+--ref-tag=<regtag>::
+	Reference Tag for Protection Information
+
+-d <data-file>::
+--data=<data-file>::
+	Data file.
+
+-M <meta>::
+--metadata=<meta>::
+	Metadata file.
+
+-p <prinfo>::
+--prinfo=<prinfo>::
+	Protection Information and check field.
+
++
+[]
+|=================
+|Bit|Description
+|3|PRACT: Protection Information Action. When set to 1, PI is stripped/inserted
+on read/write when the block format's metadata size is 8. When set to 0,
+metadata is passes.
+|2:0|PRCHK: Protection Information Check:
+|2|Set to 1 enables checking the guard tag
+|1|Set to 1 enables checking the application tag
+|0|Set to 1 enables checking the reference tag
+|=================
+
+-m <appmask>::
+--app-tag-mask=<appmask>::
+	App Tag Mask for Protection Information
+
+-a <apptag>::
+--app-tag=<apptag>::
+	App Tag for Protection Information
+
+-l::
+--limited-retry::
+	Number of limited attempts to media.
+
+-f::
+--force-unit-access::
+	FUA option to guarantee that data is stored to media.
+
+-T <type>::
+--dir-type=<type>::
+	Optional directive type. The nvme-cli only enforces the value
+	be in the defined range for the directive type, though the NVMe
+	specifcation (1.3a) defines only one directive, 01h, for write
+	stream idenfiers.
+
+-S <spec>::
+--dir-spec=<spec>::
+	Optional field for directive specifics. When used with
+	write streams, this value is defined to be the write stream
+	identifier. The nvme-cli will not validate the stream requested
+	is within the controller's capabilities.
+
+-D <dsm>::
+--dsm=<dsm>::
+	The optional data set management attributes for this command. The
+	argument for this is the lower 16 bits of the DSM field in a write
+	command; the upper 16 bits of the field come from the directive
+	specific field, if used. This may be used to set attributes for
+	the LBAs being written, like access frequency, type, latency,
+	among other things, as well as yet to be defined types. Please
+	consult the NVMe specification for detailed breakdown of how to
+	use this field.
+
+-v::
+--show-cmd::
+	Print out the command to be sent.
+
+-w::
+--dry-run::
+	Do not actually send the command. If want to use --dry-run option,
+	--show-cmd option _must_ be set. Otherwise --dry-run option will be
+	_ignored_.
+
+-t::
+--latency::
+	Print out the latency the IOCTL took (in us).
+
+EXAMPLES
+--------
+No examples yet.
+
+NVME
+----
+Part of the nvme-user suite