xbc_node_compose_key(9)

💅 NAME 💅

ok so xbc_node_compose_key — this is the XBC node key-string composer bestie, it builds the full key string for one of your XBC nodes. that's the whole vibe ✨

this little function lives in the Kernel API Manual section 9, so yeah, kernel-internals territory, bring snacks 🍓

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✨ SYNOPSIS ✨

int xbc_node_compose_key (struct xbc_node *node , char *buf , size_t
size );

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🎀 ARGUMENTS 🎀

• node — An XBC node. your main character, the one whose key we're composing 💅
• buf — A buffer to store the key. this is where the magic lands 🫶
• size — The size of the buf. don't skimp, okay? that's the capacity you're giving it 🌸

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🔥 DESCRIPTION 🔥

okay so the whole job: compose the full-length key of the node into buf. like, the whole key, not a snippet, not a teaser — the full-length one 💖

it returns the total length of the key stored in buf.

and then the two sad-girl failure modes, ngl:

• returns -EINVAL if node is NULL 😭 (can't compose a key for a node that isn't there, bestie)
• returns -ERANGE if the key depth is deeper than max depth 💀 like it went too deep, iconic but illegal

fr fr keep an eye on those two return codes, they're the vibe check of this function ✨

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🌈 SEE ALSO 🌈

kernel file ./include/linux/bootconfig.h plus all these siblings, they all slay together 🫶

• xbc_calc_checksum(9)
• xbc_node_is_value(9)
• xbc_node_is_key(9)
• xbc_node_is_array(9)
• xbc_node_is_leaf(9)
• xbc_find_value(9)
• xbc_find_node(9)
• xbc_node_get_subkey(9)
• xbc_array_for_each_value(9)
• xbc_node_for_each_child(9)
• xbc_node_for_each_subkey(9)
• xbc_node_for_each_array_value(9)
• xbc_node_for_each_key_value(9)
• xbc_for_each_key_value(9)

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ok that's the whole page, go forth and compose keys 👑

🥺 cute little sign-off: this one came from ./include/linux, stamped October 2026, and yes it's the xbc_node_compose_key(9) page — you're welcome, mwah 💜