## nng_msg_dup Duplicate a message. ### Synopsis ```c #include int nng_msg_dup(nng_msg **dup, nng_msg_t *orig); ``` ### Description The `nng_msg_dup` makes a duplicate of the original message _orig_, and saves the result in the location pointed by _dup_. The actual message body and header content is copied, but the duplicate may contain a different amount of unused space than the original message. ### Return Values This function returns 0 on success, and non-zero otherwise. ### Errors [horizontal] `NNG_ENOMEM`:: Insufficient free memory exists to duplicate a message. ### See Also xref:nng_msg_alloc.adoc[nng_msg_alloc], xref:nng_msg_free.adoc[nng_msg_free]