//  create a folder in Application Support
var path = String()

let applicationSupportDirectory = NSSearchPathDirectory.ApplicationSupportDirectory
let nsUserDomainMask = NSSearchPathDomainMask.UserDomainMask
let paths = NSSearchPathForDirectoriesInDomains( applicationSupportDirectory, nsUserDomainMask, true )
let fileManager = NSFileManager.defaultManager()

path = paths[0] + "/" + folderNameYouWant

//  check if the folder already exists
if fileManager.fileExistsAtPath( path ) == false
{
    _ = try? fileManager.createDirectoryAtPath( path,
                   withIntermediateDirectories: true,
                                    attributes: nil )
}

//  prepare content and write to file
let content = "text file content"

_ = try? content.writeToFile( path,
                  atomically: true,
                    encoding: NSUTF8StringEncoding )