Update README.md

Author: prusnak

README.md

@@ -230,7 +230,9 @@ cadaver, cauliflower, cabbage (vegetable), catalpa (tree) and Cailleach.
 * Please verify the sha256 checksums of all of your `consolidated*.pth` and corresponding converted `ggml-model-*.bin` model files to confirm that you have the correct model data files before logging an issue relating to your model files.
 
 The following command will verify if you have all possible latest files in your self-installed `./models` subdirectory:
-`llama.cpp$ sha256sum -c SHA256SUMS`
+`sha256sum --ignore-missing -c SHA256SUMS` on Linux
+or
+`shasum -a 256 --ignore-missing -c SHA256SUMS` on macOS
 
 ### Android