dns-lookup-hostname

Function

Package: socket

Arguments: name &rest rest

This function calls dns-query passing a type value of :a. This is the functional equivalent of lookup-hostname if you ignore the extra values returned. It has one additional feature, which is that if the query on name doesn't return any IP addresses, and if name doesn't contain any periods (that is, it's not a fully qualified domain name), then we try appending the values in *domain-search-list* to the name and redoing the query. Because the query can be done once for the given name and once for each name in the *domain-search-list*, this function can take longer to return than dns-query when nameservers aren't responsive.

Limitations

This function does not check a local file (often /etc/hosts) for name to IP address mappings. Thus there are cases where dns-lookup-hostname won't act just like lookup-hostname.
If a nameserver response is too large to fit in 512 bytes and is thus truncated, this function does not switch from UDP to TCP and retry the query.

See dns.htm for information on the domain naming system utility in Allegro CL and see socket.htm for general information on sockets in Allegro CL.

The documentation is described in introduction.htm and the index is in index.htm.

Created 2000.10.5.