code: function detail(drive, callback) {
      async.series(
          {
              used: function (callback) {
                  switch (os.platform().toLowerCase()) {
                      case'darwin':
                          getDetail('df -kl | grep ' + drive + ' | awk \'{print $3}\'', callback);
                          break;
                      case'linux':
                      default:
                          getDetail('df -P | grep ' + drive + ' | awk \'{print $3}\'', callback);
                  }
              },
              available: function (callback) {
                  switch (os.platform().toLowerCase()) {
                      case'darwin':
                          getDetail('df -kl | grep ' + drive + ' | awk \'{print $4}\'', callback);
                          break;
                      case'linux':
                      default:
                          getDetail('df -P | grep ' + drive + ' | awk \'{print $4}\'', callback);
                  }
              },
              mountpoint: function (callback) {
                  switch (os.platform().toLowerCase()) {
                      case'darwin':
                          getDetailNaN('df -kl | grep ' + drive + ' | awk \'{print $9}\'', function(e, d){
                              if (d) d = d.trim();
                              callback(e, d);
                          });
                          break;
                      case'linux':
                      default:
                          getDetailNaN('df -P | grep ' + drive + ' | awk \'{print $6}\'', function(e, d){
                              if (d) d = d.trim();
                              callback(e, d);
                          });
                  }
              }
          },
          function (err, results) {
              if (err) return callback(err);
              results.freePer = Number(results.available / (results.used + results.available) * 100);
              results.usedPer = Number(results.used / (results.used + results.available) * 100);
              results.total = numeral(results.used + results.available).format('0.00 b');
              results.used = numeral(results.used).format('0.00 b');
              results.available = numeral(results.available).format('0.00 b');
              results.drive = drive;
  
              callback(null, results);
          }
      );
  }
docs: Retrieve space information about one drive.
  
  @param drive
  @param callback