nvme_identi..._data_format(2)

💖 nvme_identify_ns_csi_user_data_format — the libnvme API manual, but make it cute 💖

okay bestie so libnvme has this lil function and her full government name is nvme_identify_ns_csi_user_data_format and she's here to Identify namespace user data format ✨ that's literally the whole NAME section, no notes, slay.

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✨ SYNOPSIS ✨

here's the vibe, copy it exactly, do not freestyle:

int nvme_identify_ns_csi_user_data_format (int fd , __u16
       user_data_format , __u8 uuidx , enum nvme_csi csi , void *data );

she takes five (5) arguments and she wants ALL of them, periodt 💅

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🎀 ARGUMENTS 🎀

• fd — File descriptor of nvme device. your lil doorway to the drive, keep it handy 🫶
• user_data_format — Return namespaces capability of identifier. (type is __u16 btw, iykyk)
• uuidx — UUID selection, if supported. if supported, bestie, don't come for me if your device says no 🙈
• csi — Command Set Identifier. it's an enum nvme_csi, very official of her 👑
• data — User space destination address to transfer the data. a void *, so she's flexible like that 🌸

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🌈 DESCRIPTION 🌈

so what does she actually do? she identifies the Namespace data structure for the specified User Data Format index, and that structure contains the namespace capabilities for the NVM Command Set. that's it. that's the whole job. lowkey iconic, highkey useful ✨

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💀 RETURN 💀

• the nvme command status if a response was received (peep enum nvme_status_field for the deets) ✨
• or -1 with errno set otherwise 😭

bestie if you see that -1, something went sideways and errno is spilling the tea. go check it fr fr.

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and that's the whole page, no cap, we ate and left no crumbs 🍓 this was the libnvme API manual, dated July 2026 — mwah, take care of her, she's small but mighty 💜🧚