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       Net::protoent - by-name interface to Perl's built-in getproto*() functions


        use Net::protoent;
        $p = getprotobyname(shift || 'tcp') || die "no proto";
        printf "proto for %s is %d, aliases are %s\n",
           $p->name, $p->proto, "@{$p->aliases}";

        use Net::protoent qw(:FIELDS);
        getprotobyname(shift || 'tcp') || die "no proto";
        print "proto for $p_name is $p_proto, aliases are @p_aliases\n";


       This module's default exports override the core getprotoent(), getprotobyname(), and
       getnetbyport() functions, replacing them with versions that return "Net::protoent"
       objects.  They take default second arguments of "tcp".  This object has methods that
       return the similarly named structure field name from the C's protoent structure from
       netdb.h; namely name, aliases, and proto.  The aliases method returns an array reference,
       the rest scalars.

       You may also import all the structure fields directly into your namespace as regular
       variables using the :FIELDS import tag.  (Note that this still overrides your core
       functions.)  Access these fields as variables named with a preceding "p_".  Thus,
       "$proto_obj->name()" corresponds to $p_name if you import the fields.  Array references
       are available as regular array variables, so for example "@{ $proto_obj->aliases() }"
       would be simply @p_aliases.

       The getproto() function is a simple front-end that forwards a numeric argument to
       getprotobyport(), and the rest to getprotobyname().

       To access this functionality without the core overrides, pass the "use" an empty import
       list, and then access function functions with their full qualified names.  On the other
       hand, the built-ins are still available via the "CORE::" pseudo-package.


       While this class is currently implemented using the Class::Struct module to build a
       struct-like class, you shouldn't rely upon this.


       Tom Christiansen