pslib: fix build on darwin

  nativeBuildInputs = [ cmake pkg-config ];

  buildInputs = [ zlib libpng libjpeg giflib libtiff ];

  env = lib.optionalAttrs stdenv.isDarwin {

    NIX_CFLAGS_COMPILE = "-Wno-error=implicit-function-declaration";

  };

  doCheck = true;

  outputs = [ "out" "dev" "doc" ];

  installPhase = ''

    mkdir -p $out/lib

    for path in *.so *.so.* *.o *.o.*; do

    for path in *.dylib *.so *.so.* *.o *.o.*; do

      mv $path $out/lib/

    done

    mkdir -p $dev/include

      "https://sourceforge.net/p/pslib/git/ci/master/tree/pslib/ChangeLog";

    license = licenses.gpl2;

    maintainers = with maintainers; [ ShamrockLee ];

    platforms = platforms.unix;

  };

}