anchor.diff:        "--with-machines=/etc/pdsh/machines"
         ${if readline == null then "--without-readline" else "--with-readline"}
         ${if ssh == null then "--without-ssh" else "--with-ssh"}
  -      ${if pam == null then "--without-pam" else "--with-pam"}
         ${if rsh == false then "--without-rsh" else "--with-rsh"}
         "--with-dshgroups"
         "--with-xcpu"
         "--disable-debug"
  +      '--with-rcmd-rank-list=ssh,krb4,exec,xcpu,rsh'
       )
     '';
   
  
positive.code: { stdenv, fetchurl, perl, readline, rsh, ssh, pam }:
  
  stdenv.mkDerivation rec {
    name = "pdsh-2.33";
  
negative.code:     sha256 = "0bwlkl9inj66iwvafg00pi3sk9n673phdi0kcc59y9nn55s0hs3k";
    };
  
    buildInputs = [ perl readline ssh ];
  
    preConfigure = ''
      configureFlagsArray=(
  