Function olm_sys::olm_pk_sign

pub unsafe extern "C" fn olm_pk_sign(
    sign: *mut OlmPkSigning, 
    message: *const u8, 
    message_length: usize, 
    signature: *mut u8, 
    signature_length: usize
) -> usize

Sign a message. The signature will be written to the signature buffer. Returns olm_error() on failure. If the signature buffer is too small, olm_pk_signing_last_error() will be "OUTPUT_BUFFER_TOO_SMALL".