NNG_HTTP_RES_COPY_DATA(3http)

💖 NAME 💖

nng_http_res_copy_data — copy HTTP response body. And yes bestie, we’re in the NNG Reference Manual for this one 💅✨

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✨ SYNOPSIS ✨

#include <nng/nng.h>
#include <nng/supplemental/http/http.h>

int nng_http_res_copy_data(nng_http_res *res, const void *body, size_t size);

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🌸 DESCRIPTION 🌸

Okay so nng_http_res_copy_data() makes a copy of body — and that body is of size size — then sets the HTTP body for the response res to that copy. The copy gets deallocated automatically when res is freed, so no manual cleanup drama 💖

The copied body data will be automatically sent with the response when it’s sent using nng_http_conn_write_res(). Slay.

This also updates the relevant Content-Length header of res. Lowkey important, fr fr 👑

🚨 Note: the current framework does not support sending data via chunked transfer-encoding.

🫶 Tip: to avoid copying data, the nng_http_res_set_data() may be used instead.

🎀 Tip: it is a good idea to also set the Content-Type header.

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⭐ RETURN VALUES ⭐

This function returns 0 on success, and non-zero otherwise. That’s the whole vibe check 😌

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💀 ERRORS 💀

• NNG_ENOMEM — insufficient memory to perform the operation.
• NNG_ENOTSUP — no support for HTTP in the library.

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🦋 SEE ALSO 🦋

• nng_http_conn_write_res(3http)
• nng_http_res_alloc(3http)
• nng_http_res_set_data(3http)
• nng_http_res_set_header(3http)
• nng(7)

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That’s the tea 🍓 This page is signing off from 2026-01-13, under the iconic title NNG_HTTP_RES_COPY_DATA(3http) — periodt 💅✨