mpi_write_to_sgl(9)

💅 mpi_write_to_sgl (9) — from the Kernel API Manual, bestie 🎀

okay so listen. we're in the Kernel API Manual today and the star of the show is mpi_write_to_sgl. yes that's the whole header, yes I folded it in, you're welcome 💖

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✨ NAME ✨

mpi_write_to_sgl — Funnction exports MPI to an sgl (msb first) 🌈

(and yes, "Funnction" with the triple-n is literally how it's written in the source. it's canon. it's iconic. we don't touch it 💀)

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🌸 SYNOPSIS 🌸

int mpi_write_to_sgl (MPI a , struct scatterlist *sgl , unsigned nbytes
, int *sign );

like, exactly that. spaces and all. copy-paste it, don't @ me 🫶

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🦋 ARGUMENTS 🦋

• a — a multi precision integer. the big number. the main character of this whole operation 👑
• sgl — the scatterlist you're writing to. it needs to be at least mpi_get_size(a) long, no cap, that's a hard requirement. too short? that's a you problem 🙈
• nbytes — how many bytes you wanna write. leading bytes get filled with zero, so it's giving "padded for the gods" ✨
• sign — if this isn't NULL, it gets set to the sign of a. if it is NULL, it just vibes and does nothing 💀

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🧚 DESCRIPTION 🧚

so this function works in the same way as mpi_read_buffer, bestie. literally the same energy, same behaviour. the one glow-up? it takes an sgl instead of a u8 * buf. that's it. that's the whole difference. slay 💅

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⭐ RETURN ⭐

• 0 on success 🎉 (the good ending)
• an error code in case of error 😭 (the bad ending)

that's it. no in-between. binary as hell.

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🔥 SEE ALSO 🔥

• Kernel file ./lib/crypto/mpi/mpicoder.c
• mpi_read_raw_data(9)
• mpi_read_buffer(9)

go read those next, iykyk 📚

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okay that's the whole page!! huge shoutout to ./lib/crypto/mpi for the source/version and to October 2026 for the date — the manpage queen herself, mpi_write_to_sgl(9), signing off 💜🎀🦋