An integer or a string.
A string or
A list of keywords specifying which information is required.
Multiple values corresponding to the keywords in fields, as described below.
get-service-entry looks up service in the system database. If service is an integer, it is the port number to look up. If service is a string, it is a name to look up (it may be one of the aliases).
fields specifies which information is returned. When
get-service-entry finds an entry, it returns information about it as multiple values corresponding to the keywords in fields. These keywords can be:
Return the name of the entry.
Return the port number of the entry.
Return a list of aliases of the service.
Return the protocol of the entry, as lowercase strings like "tcp" or "udp".
get-service-entrytells you what the host computer knows. The results can be quite different between computers.
nilis not the correct protocol to use.
(get-service-entry "smtp" nil) => 25
(get-service-entry 25 nil :fields '(:name :aliases)) => "smtp", ("mail")
(get-service-entry "mail" nil) => 25
LispWorks User Guide and Reference Manual - 20 Sep 2017