# nng_msg_append ## NAME nng_msg_append --- append to message body ## SYNOPSIS ```c #include int nng_msg_append(nng_msg *msg, const void *val, size_t size); int nng_msg_append_u16(nng_msg *msg, uint16_t val16); int nng_msg_append_u32(nng_msg *msg, uint32_t val32); int nng_msg_append_u64(nng_msg *msg, uint64_t val64); ``` ## DESCRIPTION The `nng_msg_append()` family of functions appends data to the end of the body of [message][msg] _msg_, reallocating it if necessary. The first function appends _size_ bytes, copying them from _val_. The remaining functions append the value specified (such as _val32_) in network-byte order (big-endian). ## RETURN VALUES These functions return 0 on success, and non-zero otherwise. ## ERRORS - `NNG_ENOMEM`: Insufficient free memory exists. ## SEE ALSO [nng_msg_alloc][nng_msg_alloc], [nng_msg_body][nng_msg_body], [nng_msg_capacity][nng_msg_capacity], [nng_msg_chop][nng_msg_chop], [nng_msg_clear][nng_msg_chop], [nng_msg_free][nng_msg_free], [nng_msg_insert][nng_msg_insert], [nng_msg_len][nng_msg_len.md], [nng_msg_reserve][nng_msg_reserve], [nng_msg_realloc][nng_msg_realloc], [nng_msg_trim][nng_msg_trim] {{#include ../refs.md}}