newlines.fsx

open System
open System.IO

let enumFiles = Seq.collect (fun p -> Directory.EnumerateFiles(".", p, SearchOption.AllDirectories))
let procFile f =
    printfn "%s" f
    let lines = File.ReadLines f
                |> Seq.map (fun l -> System.Text.RegularExpressions.Regex.Replace(l, "\r?\n", "\r\n"))
                |> Seq.toArray
    File.WriteAllLines(f, lines)

enumFiles ["*.cs"; "*.xml"; "*.config"] |> Seq.iter procFile