Does anyone use the NaCl package to sign with HMAC SHA256 but we can't find what we need.

We've naively added:

apiCryptoAuthHMACSha256Output: outByteArray input: inByteArray inputLength: inByteArrayLength key:keyByteArray
�� <apicall: long 'crypto_auth_hmacsha256' (byte* byte* ulonglong byte*) module: 'libsodium'>
�� ^self externalCallFailed

which failed with 'Unable to find function address'.

Any hint of how to do that?