ptp_check_diff8(9)

💖 ptp_check_diff8(9) — bestie edition 💖

okay so real talk, this is a page straight out of the Kernel API Manual, and it's about a tiny little helper that does One Job and does it slayfully ✨

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🌸 NAME 🌸

ptp_check_diff8 — literally computes a new checksum when you're out here altering a 64-bit field 💅

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🦋 SYNOPSIS 🦋

__wsum ptp_check_diff8 (__be64 old , __be64 new , __wsum oldsum );

no cap, that's the whole vibe check 👑

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🎀 ARGUMENTS 🎀

• old — the old field value, like the before pic 📸
• new — the new field value, the glow-up ✨
• oldsum — the previous checksum, aka where we're coming from 🫶

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💜 DESCRIPTION 💜

so basically, this function is your girl when you've changed exactly one single field and you need the new checksum. not two fields. not a whole struct. one field. main character energy only 💁‍♀️

it's similar to ip_vs_check_diff*() in ip_vs.h, iykyk 🧚

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⭐ RETURN ⭐

the updated checksum, periodt 🔥

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🌈 SEE ALSO 🌈

• Kernel file ./include/linux/ptp_classify.h
• ptp_classify_raw(9)
• ptp_parse_header(9)
• ptp_get_msgtype(9)
• ptp_header_update_correction(9)
• ptp_msg_is_sync(9)

go read those too, they're iconic, lowkey obsessed 😭💖

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🍓 ok that's the whole page, no extra lore, I promise — every flag, every argument, every reference is here and accounted for 💀✨

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and that's a wrap bestie!! this lil gem lives in ./include/linux, dated October 2026 — screenshot it, pin it, tell your friends 🎀👑💅