libnvme(9) API Manual libnvme(9)

# [NAME](#NAME)

struct nvme\_underlying\_ns\_list - Underlying Namespace List Data Structure (CNS 1Dh)

# [SYNOPSIS](#SYNOPSIS)

struct nvme\_underlying\_ns\_list {  
**\_\_le64 genctr;**  
**\_\_le16 nument;**  
**\_\_u8 rsvd10\[6];**  
**struct nvme\_underlying\_ns\_entry entries\[NVME\_UNDERLYING\_NS\_LIST\_MAX];**  
};

# [Members](#Members)

[genctr](#genctr)

Generation Counter (GENCTR)

[nument](#nument)

Number Entries (NUMENT)

[rsvd10](#rsvd10)

Reserved

[entries](#entries)

Underlying Namespace list, see *struct* *nvme\_underlying\_ns\_entry*. Reportable up to NVME\_UNDERLYING\_NS\_LIST\_MAX entries.

struct nvme\_underlying\_ns\_list October 2026

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Document: nvme_underlying_ns_list-libnvme3(2) from nvme-cli 3.2-r0 (Chainguard OS)
Source: https://github.com/linux-nvme/nvme-cli