How to Get a List of Available Wireless Networks on Linux

How can I get a list of available wireless networks on Linux?

The Wireless Tools package -- of which iwlist is a part -- also contains a Wireless Tools Helper Library. You need to include iwlib.h and link with libiw.a (i.e. add -liw). Then look up the documentation for the iw_set_ext function. The SIOCSIWSCAN parameter will be of most use. For an example of how to use this interface, take a look at the KWifiManager source in the KDE library (see: Interface_wireless_wirelessextensions::get_available_networks method). Alternatively, you can also download the Wireless Tools source code and take a look at how the iwlib iw_set_ext function is also used for scanning in iwlist.c.

As for privileges, I imagine the process will need to run as root to perform the scan. I'd love to know if this could be done otherwise as well.

Since you are using Ubuntu 8.04 the libiw-dev package should be of use.

Get list of available WiFi connections in Linux

Your confusion is justified, as the process is not really intuitive. Basically what you need to do is to first create a QDBusInterface representing NetworkManager itself. Via that object you need to get the list of the network interfaces, iterate through them, filter out the WiFi interface(s), creating a corresponding QDBusInterface, instruct the interface to scan the available networks, and then request the list of visible access points. Then you get the SSID property of each Access Point object. Here is a simple example which demonstrates the process with plain Qt:

list_ssid.pro:

QT -= gui
QT += dbus

SOURCES += list_ssid.cpp

list_ssid.cpp:

#include <QtCore/QCoreApplication>
#include <QtCore/QDebug>
#include <QtCore/QStringList>
#include <QtDBus/QtDBus>
#include <QDebug>
#include <QThread>

int main(int argc, char **argv)
{
    QCoreApplication app(argc, argv);

    // get the interface to nm    
    QDBusInterface nm("org.freedesktop.NetworkManager", "/org/freedesktop/NetworkManager",
            "org.freedesktop.NetworkManager", QDBusConnection::systemBus());
    if(!nm.isValid())
    {
        qFatal("Failed to connect to the system bus");
    }

    // get all devices
    QDBusMessage msg = nm.call("GetDevices");
    qDebug() << "GetDevices reply: " << msg << endl;
    QDBusArgument arg = msg.arguments().at(0).value<QDBusArgument>();

    if(arg.currentType() != QDBusArgument::ArrayType)
    {
        qFatal("Something went wrong with getting the device list");
    }
    QList<QDBusObjectPath> pathsLst = qdbus_cast<QList<QDBusObjectPath> >(arg);
    foreach(QDBusObjectPath p, pathsLst)
    {
        qDebug() << "DEV PATH: " << p.path();
        // creating an interface used to gather this devices properties
        QDBusInterface device("org.freedesktop.NetworkManager", p.path(),
        "org.freedesktop.NetworkManager.Device", QDBusConnection::systemBus());
        // 2 is WiFi dev, see https://people.freedesktop.org/~lkundrak/nm-docs/nm-dbus-types.html#NMDeviceType
        if (device.property("DeviceType").toInt() != 2) 
        {
            continue;
        }
        // we got a wifi device, let's get an according dbus interface
        QDBusInterface wifi_device("org.freedesktop.NetworkManager", p.path(),
        "org.freedesktop.NetworkManager.Device.Wireless", QDBusConnection::systemBus());
        // we need to call scan on the inteface prior to request the list of interfaces
        QMap<QString, QVariant> argList;
        QDBusMessage msg = wifi_device.call("RequestScan", argList);
        QThread::sleep(2); // not the best solution, but here we just wait for the scan

        // doing the actual call
        msg = wifi_device.call("GetAllAccessPoints");
        qDebug()<< "Answer for GetAllAccessPoints:  " << msg << endl << endl;
        // dig out the paths of the Access Point objects:
        QDBusArgument ap_list_arg = msg.arguments().at(0).value<QDBusArgument>();
        QList<QDBusObjectPath> ap_path_list = qdbus_cast<QList<QDBusObjectPath> >(ap_list_arg);
        // and iterate through the list
        foreach(QDBusObjectPath p ,ap_path_list)
        {
            // for each Access Point we create an interface
            QDBusInterface ap_interface("org.freedesktop.NetworkManager", p.path(),
            "org.freedesktop.NetworkManager.AccessPoint", QDBusConnection::systemBus());
            // and getting the name of the SSID
            qDebug() << "SSID: " << ap_interface.property("Ssid").toString();
        }
    }



    return 0;
}

The same using networkmanager-qt, for the sake of comparison:

CMakeLists.txt:

project(ssid_list LANGUAGES CXX)

set(CMAKE_INCLUDE_CURRENT_DIR ON)
set(CMAKE_AUTOUIC ON)
set(CMAKE_AUTOMOC ON)
set(CMAKE_AUTORCC ON)

set(CMAKE_CXX_STANDARD 11)
set(CMAKE_CXX_STANDARD_REQUIRED ON)

find_package(Qt5 REQUIRED COMPONENTS
    Core
    Gui
    Network
    DBus
)
find_package(KF5NetworkManagerQt REQUIRED)

add_executable(ssid_list
  ssid_list.cpp
)
target_link_libraries(ssid_list Qt5::Core Qt5::DBus Qt5::Network KF5::NetworkManagerQt)

ssid_list.cpp

#include <arpa/inet.h>
#include <QThread>

#include <NetworkManagerQt/Manager>
#include <NetworkManagerQt/Device>
#include <NetworkManagerQt/WirelessDevice>
#include <NetworkManagerQt/AccessPoint>

int main()
{
    // getting all of the devices, and iterate through them
    NetworkManager::Device::List list = NetworkManager::networkInterfaces();
    Q_FOREACH (NetworkManager::Device::Ptr dev, list)
    {
        if(dev->type() != NM_DEVICE_TYPE_WIFI)
        {
            //skipping non-wifi interfaces
            continue;
        }
        // creating a Wifi device with this object path
        NetworkManager::WirelessDevice wifi_dev(dev->uni());
        wifi_dev.requestScan();
        QThread::sleep(2); // still not the best solution:w
        //get the Object Path of all the visible access points
        // and iterate through
        foreach(QString ap_path, wifi_dev.accessPoints())
        {
            // creating an AccessPoint object with this path
            NetworkManager::AccessPoint ap(ap_path);
            // and finally get the SSID
            qDebug() << "SSID:" << ap.ssid();

        }
    }
}

How to show list of available Wifi networks in a DIALOG form in BASH?

You can't! Only one string for '--backtitle'.

Try this:

function forum(){
    dialog --ok-label "Submit" \
        --backtitle "Connect to wifi" \
        --title "Wifi management" \
        --form "$(nmcli dev wifi list)" \
        15 50 0 \
        "SSID:"         1 1 "$ssid"     1 10 40 0 \
        "Password:"     3 1 "$passwd"       3 10 40 0 \
    2>&1 1>&3
}

How to find all and connect all available wifi signals using python?

I think one of the best modules for wifi manipulation in python is the wifi package.

pip install wifi

Simple use case is; (replace "wlan0" with your wireless device id)

from wifi import Cell, Scheme
list(Cell.all('wlan0'))

This will return a list of Cell objects. Each object will have the following attributes:

• ssid
• signal
• quality
• frequency
• bitrates
• encrypted
• channel
• address
• mode

For cells that have encrypted as True, there will also be the following attributes:

• encryption_type

To connenc to an AP;

cell = list(Cell.all('wlan0'))[0]
scheme = Scheme.for_cell('wlan0', 'home', cell, passkey)
scheme.save()
scheme.activate()

scheme = Scheme.find('wlan0', 'home')
scheme.activate()

for more info goto https://wifi.readthedocs.io/en/latest/

Get a List of available Wireless Networks using VBA

I found a way to use the netsh commands and was able to get the results that I wanted from the following code...

Dim strNetwork As String
strNetwork = ShellRun("netsh wlan show network")

Public Function ShellRun(sCmd As String) As String

    'Run a shell command, returning the output as a string'
    Dim oShell As Object
    Set oShell = CreateObject("WScript.Shell")

    'run command'
    Dim oExec As Object
    Dim oOutput As Object
    Set oExec = oShell.Exec(sCmd)
    Set oOutput = oExec.StdOut

    'handle the results as they are written to and read from the StdOut object'
    Dim s As String
    Dim sLine As String
    While Not oOutput.AtEndOfStream
        sLine = oOutput.ReadLine
        If sLine <> "" Then s = s & sLine & vbCrLf
    Wend

    ShellRun = s

End Function

Hopefully this helps anyone in the future that is trying to do come up with a solution for something like this.

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