libnvme(9) API Manual libnvme(9)

# [NAME](#NAME)

struct nvme\_mi\_mi\_req\_hdr - MI request message header.

# [SYNOPSIS](#SYNOPSIS)

struct nvme\_mi\_mi\_req\_hdr {  
**struct nvme\_mi\_msg\_hdr hdr;**  
**\_\_u8 opcode;**  
**\_\_u8 rsvd0\[3];**  
**\_\_le32 cdw0, cdw1;**  
};

# [Members](#Members)

[hdr](#hdr)

generic MI message header

[opcode](#opcode)

opcode (OPC) for the specific MI command

[rsvd0](#rsvd0)

reserved bytes

[cdw0](#cdw0)

Management Request Doubleword 0 - command specific usage

[cdw1](#cdw1)

Management Request Doubleword 1 - command specific usage

# [Description](#Description)

Wire format for MI request message headers, defined in section 5 of NVMe-MI.

struct nvme\_mi\_mi\_req\_hdr September 2026

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Document: nvme_mi_mi_req_hdr-libnvme3(2) from nvme-cli 3.1-r0 (Chainguard OS)
Source: https://github.com/linux-nvme/nvme-cli