anchor.diff:        */Makefile{.in,.am}
     '';
   
  -  configureFlags = [
  -    "--with-gssapi"
  -    "--with-mysql"
  -  ];
  -
     preCheck = ''
       # Add missing files.
       cp ${builtins.toString readmsg-tests} readmsg/tests/
  
positive.code:   nativeBuildInputs = [
      autoreconfHook gettext libtool pkgconfig
    ] ++ stdenv.lib.optional doCheck dejagnu;
  
    buildInputs = [
      gdbm pam readline ncurses gnutls guile texinfo gnum4 sasl fribidi nettools
      gss mysql.lib
  
negative.code:     done
      # Disable comsat tests that fail without tty in the sandbox.
      tty -s || echo > comsat/tests/testsuite.at
      # Disable lmtp tests that require root spool.
      echo > maidag/tests/lmtp.at
      # Disable mda tests that require /etc/passwd to contain root.
      grep -qo '^root:' /etc/passwd || echo > maidag/tests/mda.at
      # Provide libraries for mhn.
      export LD_LIBRARY_PATH=$(pwd)/lib/.libs
    '';
    postCheck = ''
      unset LD_LIBRARY_PATH
    '';
  
    meta = with stdenv.lib; {
      description = "Rich and powerful protocol-independent mail framework";
  