anchor.diff:      [ "ac_cv_func_malloc_0_nonnull=yes"
         "ac_cv_func_realloc_0_nonnull=yes" ];
   
  -  installPhase = if stdenv.isDarwin then ''
  +  installPhase = if watchOnly then ''
       install -m 0755 -D watch $out/bin/watch
       install -m 0644 -D watch.1 $out/share/man/man1/watch.1
     '' else null;
  
positive.code:     description = "Utilities that give information about processes using the /proc filesystem";
      priority = 10; # less than coreutils, which also provides "kill" and "uptime"
      license = lib.licenses.gpl2;
      platforms = lib.platforms.linux ++ lib.platforms.cygwin ++ lib.platforms.darwin;
      maintainers = [ lib.maintainers.typetetris ];
    };
  }
  
negative.code: { lib, stdenv, fetchurl, ncurses, pkgconfig
  
  # procps is mostly Linux-only. Most commands require a running Linux
  # system (or very similar like that found in Cygwin). The one
  # exception is ‘watch’ which is portable enough to run on pretty much
  # any UNIX-compatible system.
  , watchOnly ? !(stdenv.isLinux || stdenv.isCygwin) }:
  
  stdenv.mkDerivation rec {
    name = "procps-${version}";
  