[bare-expo] Fix start-metro script on Linux

CONTRIBUTING.md

@@ -53,6 +53,8 @@ Manual smoke tests are included in `apps/native-component-list`, this is a good
    - iOS: `yarn ios`
    - Android: `yarn android`
 
+    If you are working on a Linux distribution, make sure to set the `TERMINAL` environment variable to your preferred terminal application. (e.g. `export TERMINAL="Konsole"`)
+
 8. You are now running the `test-suite` app via the `bare-expo` project. The next section explains how you can begin to make changes to SDK packages.
 
 > If this didn't work for you as described, please [open an issue.](https://github.com/expo/expo/issues/new/choose)

apps/bare-expo/scripts/start-metro.sh

@@ -21,6 +21,15 @@ yarn start --port ${port}
 EOF
   # execute the file in a new command line window
   chmod 0755 ${commandFile}
-  open ${commandFile}
-
+  case "$OSTYPE" in
+     darwin*)
+        open ${commandFile}
+        ;;
+     *)
+       # Spawns a new terminal window and detaches it
+       # Assuming the non-standard variable $TERMINAL is set
+        nohup "$TERMINAL" -e "${commandFile}" </dev/null >/dev/null 2>&1 &
+        ;;
+  esac
+
 fi