BSON_APPEND_DOCUMENT(3)

💅 BSON_APPEND_DOCUMENT(3) — the libbson glow-up

okay bestie, so this is a page straight out of libbson and it's genuinely one of the cutest little functions ever. it appends a document inside another document. nesting!! we love to see it. 🪆✨

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🌸 SYNOPSIS 🌸

#define BSON_APPEND_DOCUMENT(b, key, val) \
   bson_append_document (b, key, (int) strlen (key), val)

bool
bson_append_document (bson_t *bson,
                      const char *key,
                      int key_length,
                      const bson_t *value);

so you've got two entry points, iykyk: the macro BSON_APPEND_DOCUMENT which is literally just a lil shortcut that calls strlen on your key for you (so your key has to be a NUL-terminated C string, no funny business), and the real function bson_append_document where you pass the length yourself. main character energy. 👑

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🎀 PARAMETERS 🎀

• bson — a bson_t. this is the doc you're stuffing stuff into. the host. the parent. the mother if you will. 🫶
• key — an ASCII C string holding the name of the field. keep it ASCII, bestie, that's the assignment. ✨
• key_length — the length of key in bytes. or, and this is the fun part, pass -1 and it'll figure out the length itself with strlen(). lowkey magical. 🪄
• value — a bson_t containing the sub-document you wanna append. the child!! the baby!! 🐣

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🦋 DESCRIPTION 🦋

bson_append_document() shall append child to bson using the specified key. and like — the type of the field? it's gonna be a document. that's it. that's the vibe. a document inside a document, no cap. 💖

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🔥 RETURNS 🔥

returns true if the operation was applied successfully. slay. ✅

but — and listen, this is important — the function will fail if appending value grows bson larger than INT32_MAX. 😭 that's a hard limit, not a suggestion, so don't come crying to me when your mega-doc doesn't fit. check your return value, fr fr.

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💜 AUTHOR 💜

MongoDB, Inc — the icons who brought you this whole thing. 👑

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🌈 COPYRIGHT 🌈

2009-present, MongoDB, Inc. 🫡

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and that's the whole page, bestie!! go forth and nest those documents responsibly 💅✨

— libbson version 2.5.6, dated Oct 09, 2026 🎀 mwah, ily, bye!! 🫶