mei_write(9)

💅 mei_write(9) — Kernel API Manual energy

okay so bestie, welcome to mei_write(9) — yes that's the kernel API manual page, and yes it's about to be your new hyperfixation. this is the page for mei_write, which is, drumroll please… the write function. that's it. that's the name. iconic minimalism, honestly.

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✨ NAME ✨

mei_write — the write function. 🎀

like literally that's the whole name section. she said "I am the write function" and left. we respect it.

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🌸 SYNOPSIS 🌸

ssize_t mei_write (struct file *file , const char __user *ubuf , size_t
length , loff_t *offset );

look at her. ssize_t return type, four arguments, perfectly lined up. this is the signature, keep it exactly like this, no cap — spacing and all. 🫶

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🦋 ARGUMENTS 🦋

okay so the four besties she takes:

• file — pointer to file structure. yep, the file struct herself. 💖
• ubuf — pointer to user buffer. the actual data lives over here, in userland. 🙈
• length — buffer length. how much are we working with, bestie? 📏
• offset — data offset in buffer. where in the buffer we're starting, iykyk. ✨

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⭐ RETURN ⭐

• >=0 — data length on success 💖 (so zero is a win too, don't come for her)
• <0 — on error 😭

that's it. success gives you back the data length, error gives you a negative number. vibe check passed or vibe check failed, no in-between. 💀

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🌈 SEE ALSO 🌈

grab a snack, this list is long and she's worth it. the Kernel file behind all this is ./drivers/misc/mei/main.c, and here's the whole crew:

mei_open(9), mei_cl_vtag_remove_by_fp(9), mei_release(9), mei_read(9), mei_cl_vtag_by_fp(9), mei_ioctl_connect_client(9), mei_vt_support_check(9), mei_ioctl_connect_vtag(9), mei_ioctl_client_notify_request(9), mei_ioctl_client_notify_get(9), mei_ioctl(9), mei_poll(9), mei_cl_is_write_queued(9), mei_fsync(9), mei_fasync(9), trc_show(9), fw_status_show(9), hbm_ver_show(9), hbm_ver_drv_show(9), fw_ver_show(9), dev_state_show(9), mei_set_devstate(9), kind_show(9), mei_minor_get(9), mei_minor_free(9)

twenty-five references. twenty-five. she's connected like that. 👑

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okay that's the whole page, bestie — mwah 💋. this little gem lives in ./drivers/misc/mei, it's dated October 2026, and it's your mei_write(9) from the Kernel API Manual. go write something iconic. 🧚💜