subbuf_start_reserve(9)

✨ subbuf_start_reserve ✨

Okay bestie, so this one is from the Kernel API Manual (yes, the kernel has a manual, we're literally living in the future 💅). Buckle up, it's a short one but it's giving very "small function, big job" energy.

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🌸 NAME 🌸

subbuf_start_reserve — reserve bytes at the start of a sub-buffer 🎀

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🦋 SYNOPSIS 🦋

void subbuf_start_reserve (struct rchan_buf *buf , size_t length );

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⭐ ARGUMENTS ⭐

• buf — the relay channel buffer, aka the vibe container you're working in 🫶
• length — how many bytes you wanna reserve, no cap 🔥

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💖 DESCRIPTION 💖

So basically it's a helper function 😌. Its whole thing is reserving bytes at the beginning of a sub-buffer — and it does this inside the subbuf_start callback. That's the moment. That's its main character moment. ✨

Lowkey iconic that such a tiny function gets to live inside a callback, but slay. 👑

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🌈 SEE ALSO 🌈

The kernel file ./include/linux/relay.h is the home base 🏠, and also go check out relay_write(9), __relay_write(9), and relay_reserve(9) — the whole relay squad fr fr 💜

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Heads up bestie: all of this lives down in ./include/linux, so don't come looking for it anywhere else 🙈

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Okay that's the whole page 🎉 — huge shoutout to ./include/linux and the October 2026 edition of the Kernel API Manual for blessing us with this one. Go reserve some bytes, you got this 💅🍓💖