# NDCTL User Guide

## Introduction

`ndctl` is a utility for managing the Linux LIBNVDIMM Kernel subsystem. It is designed to work with various non-volatile memory devices (NVDIMMs) from different vendors. The LIBNVDIMM subsystem defines a kernel device model and control message interface for platform NVDIMM resources like those defined by the [ACPI v6.0](http://www.uefi.org/sites/default/files/resources/ACPI_6_0_Errata_A.PDF) NFIT (**N**VDIMM **F**irmware **I**nterface **T**able). The latest [ACPI ](http://www.uefi.org/specifications)and [UEFI ](http://www.uefi.org/specifications)specifications can be found at [uefi.org](http://www.uefi.org). Operations supported by `ndctl` include:

* Provisioning capacity (namespaces)
* Enumerating Devices
* Enabling and Disabling NVDIMMs, Regions, and Namespaces
* Managing NVDIMM Labels

## What's new in v68

This release incorporates functionality up to the 5.6 kernel.

Highlights for this release include new commands to read-infoblock and write-infoblock, improvements and tests related to alignment constraints, misc build/compilation related fixes, and misc usability and documentation fixes.

Commands: 

* [zero-labels](/ndctl-user-guide/v68/ndctl-man-pages/ndctl-zero-labels.md): display an error if regions are active 
* destroy-namespace: fix seed namespace accounting 
* [list](/ndctl-user-guide/v68/ndctl-man-pages/ndctl-list.md): drop named list objects from verbose listing 
* \*-namespace: emit better errors on failure 
* [read-infoblock](/ndctl-user-guide/v68/ndctl-man-pages/ndctl-read-infoblock.md): new command to read an infoblock 
* [write-infoblock](/ndctl-user-guide/v68/ndctl-man-pages/ndctl-write-infoblock.md): new command to create and write an infoblock

APIs: 

* ndctl\_namespace\_get\_target\_node 
* ndctl\_namespace\_is\_configuration\_idle 
* ndctl\_region\_get\_align
* ndctl\_region\_get\_target\_node 
* ndctl\_region\_set\_align


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