NNG_MSG_CHOP(3)

💖 NNG_MSG_CHOP 💖

okay bestie, so this is nng_msg_chop(3) from the NNG Reference Manual — the lil' family of functions that says "bye bye" to data at the end of a message body 🫶

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✨ NAME ✨

nng_msg_chop — remove data from end of message body 🍓

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✨ SYNOPSIS ✨

#include <nng/nng.h>

int nng_msg_chop(nng_msg *msg, size_t size);
int nng_msg_chop_u16(nng_msg *msg, uint16_t *val16);
int nng_msg_chop_u32(nng_msg *msg, uint32_t *val32);
int nng_msg_chop_u64(nng_msg *msg, uint64_t *val64);

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✨ DESCRIPTION ✨

so the nng_msg_chop() family? it's giving scissors but for messages ✂️✨ These functions remove data from the end of the body of message msg. Not the front, bestie — the end. If you wanted the front, that's a whole other function, and yes it's in SEE ALSO, iykyk 💅

here's the vibe breakdown:

• the first one, nng_msg_chop(), removes size bytes. just... gone. bye 💨
• the remaining ones remove 2, 4, or 8 bytes, and then stores them in the value (like val32) — but plot twist — after converting them from network-byte order (big-endian) to native byte order 🔄👑

so like, it doesn't just yeet the bytes into the void, it hands them to you all nicely converted. the way that it's both a delete AND a read? main character behavior, fr fr 👑

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✨ RETURN VALUES ✨

these functions return 0 on success, and non-zero otherwise 🎀 (as is the way of Unix, no cap)

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✨ ERRORS ✨

• NNG_EINVAL — the message body is too short to remove the requested data 😭 like bestie you cannot chop what isn't there. there's just not enough message to go around.

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✨ SEE ALSO ✨

nng_msg_alloc(3), nng_msg_append(3), nng_msg_body(3), nng_msg_free(3), nng_msg_insert(3), nng_msg_len(3), nng_msg_capacity(3), nng_msg_reserve(3), nng_msg_realloc(3), nng_msg_trim(3), nng_strerror(3), nng_msg(5), nng(7)

ok real talk for one sec 🫶 if your body is too short for whatever you asked to chop, you're getting NNG_EINVAL and nothing else happens. check your lengths first, diva. no guessing, just facts.

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that's the whole page, babe ✨ go forth and chop responsibly 🌸

mwah 💋 — this was NNG_MSG_CHOP(3) from the NNG Reference Manual, dated 2026-06-30. slay, bye 👑🦋