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nvme-id-ns-lba-format(1)
========================

NAME
----
nvme-id-ns-lba-format - Send NVMe Identify Namespace for the specified LBA Format index, display structure

SYNOPSIS
--------
[verse]
'nvme id-ns' <device> [--uuid-index=<uuid-index> | -U <uuid_index>]
			[--lba-format-index=<lba_format_index> | -i <lba_format_index>]
			[--verbose | -v]
			[--output-format=<fmt> | -o <fmt>] [--verbose | -v]

DESCRIPTION
-----------
For the NVMe device given, sends an identify namespace for
the specified LBA Format index command and provides the result
that is include capability field only and returned structure.

The <device> parameter is mandatory and may be either the NVMe character
device (ex: /dev/nvme0), or a namespace block device (ex: /dev/nvme0n1).

On success, the structure may be returned in one of several ways depending
on the option flags; the structure may be parsed by the program or the
raw buffer may be printed to stdout.

OPTIONS
-------
-U <uuid-index>::
--uuid-index=<uuid-index>::
	UUID Index of the feature

-i <lba_format_index>::
--lba-format-index=<lba_format_index>::
	This field specifies the index into the LBA Format list identifying
	the LBA Format capabilities that are to be returned

-v::
--verbose::
	Increase the information detail in the output.

-o <fmt>::
--output-format=<fmt>::
	Set the reporting format to 'normal', 'json' or 'binary'. Only one
	output format can be used at a time.

EXAMPLES
--------
* Has the program interpret the returned buffer and display the known
fields in a human readable format:
+
------------
# nvme id-ns-lba-format /dev/nvme0n1 -i 0
------------
+
* Have the program return the raw structure in binary:
+
------------
# nvme id-ns-lba-format /dev/nvme0n1 -i 0 -o binary > id_ns.raw
# nvme id-ns-lba-format /dev/nvme0n1 -i 0 --output-format=binary > id_ns.raw
------------
+
It is probably a bad idea to not redirect stdout when using this mode.

* Alternatively you may want to send the data to another program that
can parse the raw buffer.
+
------------
# nvme id-ns-lba-format /dev/nvme0n1 -i 0 --raw-binary | nvme_parse_id_ns
------------
+
The parse program in the above example can be a program that shows the
structure in a way you like. The following program is such an example
that will parse it and can accept the output through a pipe, `'|'`,
as shown in the above example, or you can `'cat'` a saved output buffer
to it.
------------
/* File: nvme_parse_id_ns_lba_format.c */

#include <linux/nvme.h>
#include <stdio.h>
#include <unistd.h>

int main(int argc, char **argv)
{
	unsigned char buf[sizeof(struct nvme_id_ns)];
	struct nvme_id_ns *ns = (struct nvme_id_ns *)buf;

	if (read(STDIN_FILENO, buf, sizeof(buf)))
		return 1;

	printf("nsze : %#llx\n", ns->nlbaf);
	printf("ncap : %#llx\n", ns->mc);
	return 0;
}
------------

NVME
----
Part of the nvme-user suite