Interface(3) User Contributed Perl Documentation Interface(3)NAMEIO::Interface - Perl extension for access to network card configuration
information
SYNOPSIS
# ======================
# the new, preferred API
# ======================
use IO::Interface::Simple;
my $if1 = IO::Interface::Simple->new('eth0');
my $if2 = IO::Interface::Simple->new_from_address('127.0.0.1');
my $if3 = IO::Interface::Simple->new_from_index(1);
my @interfaces = IO::Interface::Simple->interfaces;
for my $if (@interfaces) {
print "interface = $if\n";
print "addr = ",$if->address,"\n",
"broadcast = ",$if->broadcast,"\n",
"netmask = ",$if->netmask,"\n",
"dstaddr = ",$if->dstaddr,"\n",
"hwaddr = ",$if->hwaddr,"\n",
"mtu = ",$if->mtu,"\n",
"metric = ",$if->metric,"\n",
"index = ",$if->index,"\n";
print "is running\n" if $if->is_running;
print "is broadcast\n" if $if->is_broadcast;
print "is p-to-p\n" if $if->is_pt2pt;
print "is loopback\n" if $if->is_loopback;
print "is promiscuous\n" if $if->is_promiscuous;
print "is multicast\n" if $if->is_multicast;
print "is notrailers\n" if $if->is_notrailers;
print "is noarp\n" if $if->is_noarp;
}
# ===========
# the old API
# ===========
use IO::Socket;
use IO::Interface qw(:flags);
my $s = IO::Socket::INET->new(Proto => 'udp');
my @interfaces = $s->if_list;
for my $if (@interfaces) {
print "interface = $if\n";
my $flags = $s->if_flags($if);
print "addr = ",$s->if_addr($if),"\n",
"broadcast = ",$s->if_broadcast($if),"\n",
"netmask = ",$s->if_netmask($if),"\n",
"dstaddr = ",$s->if_dstaddr($if),"\n",
"hwaddr = ",$s->if_hwaddr($if),"\n";
print "is running\n" if $flags & IFF_RUNNING;
print "is broadcast\n" if $flags & IFF_BROADCAST;
print "is p-to-p\n" if $flags & IFF_POINTOPOINT;
print "is loopback\n" if $flags & IFF_LOOPBACK;
print "is promiscuous\n" if $flags & IFF_PROMISC;
print "is multicast\n" if $flags & IFF_MULTICAST;
print "is notrailers\n" if $flags & IFF_NOTRAILERS;
print "is noarp\n" if $flags & IFF_NOARP;
}
my $interface = $s->addr_to_interface('127.0.0.1');
DESCRIPTIONIO::Interface adds methods to IO::Socket objects that allows them to be
used to retrieve and change information about the network interfaces on
your system. In addition to the object-oriented access methods, you
can use a function-oriented style.
THIS API IS DEPRECATED. Please see IO::Interface::Simple for the
preferred way to get and set interface configuration information.
Creating a Socket to Access Interface Information
You must create a socket before you can access interface information.
The socket does not have to be connected to a remote site, or even used
for communication. The simplest procedure is to create a UDP protocol
socket:
my $s = IO::Socket::INET->new(Proto => 'udp');
The various IO::Interface functions will now be available as methods on
this socket.
Methods
@iflist = $s->if_list
The if_list() method will return a list of active interface names,
for example "eth0" or "tu0". If no interfaces are configured and
running, returns an empty list.
$addr = $s->if_addr($ifname [,$newaddr])
if_addr() gets or sets the interface address. Call with the
interface name to retrieve the address (in dotted decimal format).
Call with a new address to set the interface. In the latter case,
the routine will return a true value if the operation was
successful.
my $oldaddr = $s->if_addr('eth0');
$s->if_addr('eth0','192.168.8.10') || die "couldn't set address: $!";
Special case: the address of the pseudo-device "any" will return
the IP address "0.0.0.0", which corresponds to the INADDR_ANY
constant.
$broadcast = $s->if_broadcast($ifname [,$newbroadcast]
Get or set the interface broadcast address. If the interface does
not have a broadcast address, returns undef.
$mask = $s->if_netmask($ifname [,$newmask])
Get or set the interface netmask.
$dstaddr = $s->if_dstaddr($ifname [,$newdest])
Get or set the destination address for point-to-point interfaces.
$hwaddr = $s->if_hwaddr($ifname [,$newhwaddr])
Get or set the hardware address for the interface. Currently only
ethernet addresses in the form "00:60:2D:2D:51:70" are accepted.
$flags = $s->if_flags($ifname [,$newflags])
Get or set the flags for the interface. The flags are a bitmask
formed from a series of constants. See "Exportable constants"
below.
$ifname = $s->addr_to_interface($ifaddr)
Given an interface address in dotted form, returns the name of the
interface associated with it. Special case: the INADDR_ANY
address, 0.0.0.0 will return a pseudo-interface name of "any".
EXPORT
IO::Interface exports nothing by default. However, you can import the
following symbol groups into your namespace:
:functions Function-oriented interface (see below)
:flags Flag constants (see below)
:all All of the above
Function-Oriented Interface
By importing the ":functions" set, you can access IO::Interface in a
function-oriented manner. This imports all the methods described above
into your namespace. Example:
use IO::Socket;
use IO::Interface ':functions';
my $sock = IO::Socket::INET->new(Proto=>'udp');
my @interfaces = if_list($sock);
print "address = ",if_addr($sock,$interfaces[0]);
Exportable constants
The ":flags" constant imports the following constants for use with the
flags returned by if_flags():
IFF_ALLMULTI
IFF_AUTOMEDIA
IFF_BROADCAST
IFF_DEBUG
IFF_LOOPBACK
IFF_MASTER
IFF_MULTICAST
IFF_NOARP
IFF_NOTRAILERS
IFF_POINTOPOINT
IFF_PORTSEL
IFF_PROMISC
IFF_RUNNING
IFF_SLAVE
IFF_UP
This example determines whether interface 'tu0' supports multicasting:
use IO::Socket;
use IO::Interface ':flags';
my $sock = IO::Socket::INET->new(Proto=>'udp');
print "can multicast!\n" if $sock->if_flags & IFF_MULTICAST.
AUTHOR
Lincoln Stein <lstein@cshl.org>
This module is distributed under the same license as Perl itself.
SEE ALSOperl(1), IO::Socket(3), IO::Multicast(3), IO::Interface::Simple
perl v5.14.0 2008-06-06 Interface(3)
