code: function listNetInterfaces() {
      return new Promise((ac, rj) => {
          exec('nmcli d', (err, stdout, stderr) => {
              const lines = stdout.split('\n');
              if (err || lines.length<2) {
                  rj({error: 'No network available.'});
                  return;
              }
  
              lines.shift();
              // Correct visible APs should be listed
              let bWlanExist = false;
              const interfaces = [];
              lines.forEach((line)=>{
                  let sp = line.trim().split(/\s+/);
                  if (sp.length < 4 || sp[0]=='lo') return; // Illegally formatted line
                  if (sp[0].indexOf('wlan')==0) bWlanExist = true;
                  interfaces.push(sp[0]);
              });
  
              ac([interfaces, bWlanExist]);
          });
      });
  }
docs: List Network Interfaces
  @return {Promise} Return a list of network interfaces and whether you are using WiFi