Net::servent(3) Perl Programmers Reference Guide Net::servent(3)NAMENet::servent - by-name interface to Perl's built-in get
serv*() functions
SYNOPSIS
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 $s_port, aliases are @s_aliases\n";
DESCRIPTION
This module's default exports override the core getser_
vent(), getservbyname(), and getnetbyport() functions,
replacing them with versions that return "Net::servent"
objects. They take default second arguments of "tcp".
This object has methods that return the similarly named
structure field name from the C's servent structure from
netdb.h; namely name, aliases, port, and proto. The
aliases method returns an array reference, the rest
scalars.
You may also import all the structure fields directly into
your namespace as regular variables using the :FIELDS
import tag. (Note that this still overrides your core
functions.) Access these fields as variables named with a
preceding "n_". Thus, "$serv_obj->name()" corresponds to
$s_name if you import the fields. Array references are
available as regular array variables, so for example "@{
$serv_obj->aliases() }" would be simply @s_aliases.
The getserv() function is a simple front-end that forwards
a numeric argument to getservbyport(), and the rest to
getservbyname().
To access this functionality without the core overrides,
pass the "use" an empty import list, and then access func
tion functions with their full qualified names. On the
other hand, the built-ins are still available via the
"CORE::" pseudo-package.
EXAMPLES
use Net::servent qw(:FIELDS);
while (@ARGV) {
my ($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;
}
NOTE
While this class is currently implemented using the
Class::Struct module to build a struct-like class, you
shouldn't rely upon this.
AUTHOR
Tom Christiansen
2001-02-22 perl v5.6.1 Net::servent(3)
