anchor.diff:  %% <a href="http://api.zeromq.org/master:zmq_connect">zmq_connect</a></i>
   -type erlzmq_endpoint() :: string().
   
  -%% @type errno() = eperm | enoent | srch | eintr | eio | enxio | ebad |
  -%% echild | edeadlk | enomem | eacces | efault | enotblk | ebusy | eexist |
  -%% exdev | enodev | enotdir | eisdir | einval | enfile | emfile | enotty |
  -%% etxtbsy | efbig | enospc | espipe | erofs | emlink | epipe | eagain |
  -%% einprogress | ealready | enotsock | edestaddrreq | emsgsize |
  -%% eprototype | enoprotoopt | eprotonosupport | esocktnosupport |
  -%% enotsup | epfnosupport | eafnosupport | eaddrinuse | eaddrnotavail |
  -%% enetdown | enetunreach | enetreset | econnaborted | econnreset |
  -%% enobufs | eisconn | enotconn | eshutdown | etoomanyrefs | etimedout |
  -%% econnrefused | eloop | enametoolong.
   %% Standard error atoms.
   -type errno() :: eperm | enoent | srch | eintr | eio | enxio | ebad |
                    echild | edeadlk | enomem | eacces | efault | enotblk |
  
positive.code: %% <a href="http://api.zeromq.org/master:zmq_recv">zmq_recv</a></i>
  -type erlzmq_send_recv_flag() :: dontwait | sndmore | recvmore | {timeout, timeout()}.
  
  %% @type erlzmq_send_recv_flags() = list(erlzmq_send_recv_flag()).
  %% A list of flags to use with {@link ezqm:send/3. send/3} and
  %% {@link erlzmq:recv/2. recv/2}
  -type erlzmq_send_recv_flags() :: list(erlzmq_send_recv_flag()).
  
  %% @type erlzmq_sockopt() = hwm | swap | affinity | identity | subscribe |
  %% unsubscribe | rate | recovery_ivl | mcast_loop | sndbuf | rcvbuf |
  %% rcvmore | fd | events | linger | reconnect_ivl | backlog |
  %% | reconnect_ivl_max.
  %% Available options for {@link erlzmq:setsockopt/3. setsockopt/3}
  %% and {@link erlzmq:getsockopt/2. getsockopt/2}.<br />
  %% <i>For more information see
  
negative.code:                           ipv4only.
  
  
  %% Possible option values for {@link erlzmq:setsockopt/3. setsockopt/3}.
  -type erlzmq_sockopt_value() :: integer() | iolist().
  
  