anchor.diff:  { lib, stdenv, nixosTests, fetchpatch, fetchFromGitHub, autoreconfHook, libxslt
   , libxml2 , docbook_xml_dtd_45, docbook_xsl, itstool, flex, bison, runtimeShell
  -, pam ? null, glibcCross ? null
  +, libxcrypt, pam ? null, glibcCross ? null
   }:
   
   let
  
positive.code:   configureFlags = [
      "--enable-man"
      "--with-group-name-max-length=32"
    ] ++ lib.optional (stdenv.hostPlatform.libc != "glibc") "--disable-nscd";
  
    preBuild = lib.optionalString (stdenv.hostPlatform.libc == "glibc")
  
negative.code:     sha256 = "sha256-PxLX5V0t18JftT5wT41krNv18Ew7Kz3MfZkOi/80ODA=";
    };
  
    buildInputs = [ libxcrypt ]
      ++ lib.optional (pam != null && stdenv.isLinux) pam;
    nativeBuildInputs = [autoreconfHook libxslt libxml2
      docbook_xml_dtd_45 docbook_xsl flex bison itstool
      ];
  