# Obtaining the device list

Note: There may be network devices that cannot be opened by the process calling Service.interfaces(), because, for example, that process does not have sufficient privileges to open them for capturing; if so, those devices will not appear on the list.

Docs[: libpcap](https://www.tcpdump.org/manpages/pcap.3pcap.html), [javadoc](https://javadoc.io/doc/com.ardikars.pcap/pcap-spi/latest/pcap/spi/Service.html).

{% tabs %}
{% tab title="Java" %}

```
public static void main(String[] _args) throws ErrorException {
  var service = Service.Creator.create("PcapService");
  Iterator<Interface> devices = service.interfaces().iterator();
  while (devices.hasNext()) {
    Interface device = devices.next();
    System.out.println("Name             : " + device.name());
    System.out.println("Description      : " + device.description());
    System.out.println("Flags            : " + device.flags());
    if (device.addresses() != null) {
      System.out.println("Addresses        : ");
      Iterator<Address> addresses = device.addresses().iterator();
      while (addresses.hasNext()) {
        Address address = addresses.next();
        System.out.println("\tAddress      : " + address.address());
        System.out.println("\tNetmask      : " + address.netmask());
        System.out.println("\tBroadcast    : " + address.broadcast());
        System.out.println("\tDestination  : " + address.destination());
      }
    }
    System.out.println();
  }
}
```

{% endtab %}

{% tab title="Kotlin" %}

```
fun main() {
  val service = Service.Creator.create("PcapService")
  val devices: Iterator<Interface> = service.interfaces().iterator()
  while (devices.hasNext()) {
    val device = devices.next()
    println("Name             : " + device.name())
    println("Description      : " + device.description())
    println("Flags            : " + device.flags())
    if (device.addresses() != null) {
      println("Addresses        : ")
      val addresses: Iterator<Address> = device.addresses().iterator()
      while (addresses.hasNext()) {
        val address: Address = addresses.next()
        System.out.println("\tAddress      : " + address.address())
        System.out.println("\tNetmask      : " + address.netmask())
        System.out.println("\tBroadcast    : " + address.broadcast())
        System.out.println("\tDestination  : " + address.destination())
      }
    }
    println()
  }
}
```

{% endtab %}

{% tab title="Scala" %}

```
def main(args: Array[String]): Unit = {
  val service = Service.Creator.create("PcapService")
  val devices = service.interfaces.iterator
  while ( {
    devices.hasNext
  }) {
    val device = devices.next
    System.out.println("Name             : " + device.name)
    System.out.println("Description      : " + device.description)
    System.out.println("Flags            : " + device.flags)
    if (device.addresses != null) {
      System.out.println("Addresses        : ")
      val addresses = device.addresses.iterator
      while ( {
        addresses.hasNext
      }) {
        val address = addresses.next
        System.out.println("\tAddress      : " + address.address)
        System.out.println("\tNetmask      : " + address.netmask)
        System.out.println("\tBroadcast    : " + address.broadcast)
        System.out.println("\tDestination  : " + address.destination)
      }
    }
    System.out.println()
  }
}
```

{% endtab %}

{% tab title="Clojure" %}

```
(defn print_addresses [addresses]
  (println "Addresses        :")
  (while (.hasNext addresses)
    (def address (.next addresses))
    (println "\tAddreess      :" (.address address))
    (println "\tNetmask       :" (.netmask address))
    (println "\tBroadcast     :" (.broadcast address))
    (println "\tDestination   :" (.destination address))))

(defn -main
  [& args]
  (def service (. Service$Creator (create "PcapService")))
  (def devices (.iterator (.interfaces service)))
  (while (.hasNext devices)
    (def device (.next devices))
    (println "Name             :" (.name device))
    (println "Description      :" (.description device))
    (println "Flags            :" (.flags device))
    (if (some? (.addresses device))
      (print_addresses (.iterator (.addresses device))))))
```

{% endtab %}
{% endtabs %}


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