use Net::servent;
$s = getservbyname(shift || 'ftp') || die "no service";
printf "port for %s is %s, aliases are %s\n",
$s->name, $s->port, "@{$s->aliases}";
use Net::servent qw(:FIELDS); getservbyname(shift || 'ftp') || die "no service"; print "port for $s_name is $s_port, aliases are @s_aliases\n";
getservent,
getservbyname, and getnetbyport functions,
replacing them with versions that return ``Net::servent'' objects. They
take default second arguments of ``tcp''. This object has methods that
return the similarly named structure field name from the C's servent
structure from netdb.h; namely name, aliases, port, 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
n_. Thus, $serv_obj->name corresponds to $s_name if you import the fields. Array
references are available as regular array variables, so for example @{ $serv_obj->aliases
} would be simply @s_aliases.
The getserv function is a simple front-end that forwards a
numeric argument to getservbyport, and the rest to
getservbyname.
To access this functionality without the core overrides, pass the use an empty import list, and then access function functions with their full
qualified names. On the other hand, the built-ins are still available via
the CORE:: pseudo-package.
use Net::servent qw(:FIELDS);
while (@ARGV) {
my ($service, $proto) = ((split m!/!, shift), 'tcp');
my $valet = getserv($service, $proto);
unless ($valet) {
warn "$0: No service: $service/$proto\n"
next;
}
printf "service $service/$proto is port %d\n", $valet->port;
print "alias are @s_aliases\n" if @s_aliases;
}