macos - Launch shell script on login in Mac OS (OS X)

Question

I have this shell script Test.sh:

#! /bin/bash

FILE_TO_CHECK="/Users/test/start.txt"
EXIT=0

while [ $EXIT -eq 0 ]; do
    if [ -f "$FILE_TO_CHECK" ]
        then
        /usr/bin/java -jar myapp.jar
        EXIT=1
    else
        sleep 30
    fi
done

I need to start this script automatically after login.
So I put it inside a folder Test in /System/Library/StartupItems/

When I reboot the Mac, nothing happens after I log in. Any clue?

I also tried Automator, but with the same result: the java program is not running.

Answer 1

Ivan Kovacevic's pointers, especially the superuser.com link, are helpful; since at least OS X 10.9.2, your options for creating run-at-login scripts are:

Note: The methods are annotated with respect to whether they are:

• specific to a given user ("[user-SPECIFIC]"); i.e., the installation must be performed for each user, if desired; scripts are typically stored in a user-specific location, and root (administrative) privileges are NOT required for installation.
• effective for ALL users ("[ALL users]"); i.e., the installation takes effect for ALL users; scripts are typically stored in a shared location and root (administrative) privileges ARE required for installation.

The scripts themselves will run invisibly, but - with the exception of the com.apple.loginwindow login-hook method - you can open applications visibly from them; things to note:

• There is no guarantee that any such application will be frontmost, so it may be obscured by other windows opened during login.

• If you want to run another shell script visibly, simply use open /path/to/your-script, which will open it in Terminal.app; however, the Terminal window will automatically close when your script terminates.

---

Automator [user-SPECIFIC]:

• File > New, type Application
• Add a Run Shell Script action, which adds an embedded bash script, and either paste your script code there or add a command that invokes an existing script from there.

• Save the *.app bundle and add it to the Login Items list in System Preferences > User & Groups > Login Items.

  Note:

  • The embedded script runs with the default "C" locale.
  • $PATH is fixed to /usr/bin:/bin:/usr/sbin:/sbin, which notably does NOT include /usr/local/bin
  • The working dir. is the current user's home directory.

---

com.apple.loginwindowlogin hook [ALL users - DEPRECATED, but still works]:

If you have admin privileges, this is the easiest method, but it is DEPRECATED, for a variety of reasons (security, limited to a single, shared script, synchronous execution); Apple especially cautions against use of this mechanism as part of a software product.

• Place your script, e.g., Test.sh, in a shared location - e.g., /Users/Shared - and make sure it is executable (chmod +x /Users/Shared/Test.sh).

• From Terminal.app, run the following:

  sudo defaults write com.apple.loginwindow LoginHook /Users/Shared/Test.sh

• Note:

  • The script will run as the root user, so exercise due caution.
    Among the methods listed here, this is the only way to run a script as root.

  • There's only one system-wide login hook.

    • Note that there's also a log-OUT hook, LogoutHook, which provides run-at-logout functionality - unlike the other approaches.

  • The login-hook script runs synchronously before other login actions, and should therefore be kept short.

    • Notably, it runs before the desktop is displayed; you cannot launch applications from the script, but you can create simple interactions via osascript and AppleScript snippets (e.g., osascript -e 'display dialog "Proceed?"'); however, any interactions block the login process.

  • The script runs in the context of the root user and he username of the user logging on is passed as the 1st argument to the script.

  • The script runs with the default "C" locale.
  • $PATH is fixed to /usr/bin:/bin:/usr/sbin:/sbin, which notably does NOT include /usr/local/bin
  • The working dir. is /.

---

launchd agents:

launchd-agent-executed scripts can be installed for a SPECIFIC user OR for ALL users - the latter requires administrative privileges.

While using launchd is Apple's preferred method, it's also the most cumbersome, as it requires creating a separate *.plist configuration file.
On the upside, you can install multiple scripts independently.

• Note:
  • No specific timing or sequencing of launchd scripts is guaranteed; loosely speaking, they "run at the same time at login"; there is even no guaranteed timing between the user-specific and the all-user tasks.
  • The script runs with the default "C" locale.
  • $PATH is fixed to /usr/bin:/bin:/usr/sbin:/sbin, which notably does NOT include /usr/local/bin
  • The working dir. is / by default, but you can configure it via the .plist file - see below.
  • The script-file path must be specified as a full, literal path (e.g., /Users/jdoe/script.sh; notably , ~-prefixed paths do not work.
  • For a description of all keys that can be used in *.plist configuration files, see man launchd.plist.
  • Both user-specific and all-users tasks run as the current user (the user logging on).

---

launchd [user-SPECIFIC]:

• Note: Lingon 3 ($5 as of early 2014) is a GUI application that facilitates the process below, but only for user-specific scripts.
• Place your script, e.g., Test.sh, in your home folder, e.g., /Users/jdoe

• Create a file with extension .plist in ~/Library/LaunchAgents, e.g., ~/Library/LaunchAgents/LoginScripts.Test.plist, by running the following in Terminal.app:

  touch ~/Library/LaunchAgents/LoginScripts.Test.plist
  

• Open the file and save it with the following content:

  <?xml version="1.0" encoding="UTF-8"?>
  <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
  <plist version="1.0">
  <dict>
      <key>Label</key>
        <!-- YOUR SELF-CHOSEN *UNIQUE* LABEL (TASK ID) HERE -->
      <string>LoginScripts.Test.sh</string>
      <key>ProgramArguments</key>
      <array>
            <!-- YOUR *FULL, LITERAL* SCRIPT PATH HERE -->
          <string>/Users/jdoe/Test.sh</string>
      </array>
      <key>RunAtLoad</key>
      <true/>
  </dict>
  </plist>
  

• The <!-- ... --> comments indicate the places to customize; you're free to choose a label, but it should be unique - ditto for the .plist filename; for simplicity, keep the label and the filename root the same.

• From Terminal.app, run the following:

  launchctl load ~/Library/LaunchAgents/LoginScripts.Test.plist
  

• Note that, as a side effect, the script will execute right away. From that point on, the script will execute whenever the CURRENT user logs on.

• It is not strictly necessary to run launchctl load -- since, by virtue of the file's location, it will be picked up automatically on next login -- but it's helpful for verifying that the file loads correctly.

---

launchd [ALL users]

• Place your script, e.g., Test.sh, in a SHARED location, e.g., /Users/Shared

• Create a file with extension .plist in /Library/LaunchAgents (requires admin privileges), e.g., /Library/LaunchAgents/LoginScripts.Test.plist, by running the following in Terminal.app:

  sudo touch /Library/LaunchAgents/LoginScripts.Test.plist
  

• Open the file and save it with the following content (make sure your text editor prompts for admin privileges on demand; alternatively, use sudo nano /Library/LaunchAgents/LoginScripts.Test.plist):

  <?xml version="1.0" encoding="UTF-8"?>
  <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
  <plist version="1.0">
  <dict>
      <key>Label</key>
        <!-- YOUR SELF-CHOSEN *UNIQUE* LABEL (TASK ID) HERE -->
      <string>LoginScripts.Test.sh</string>
      <key>ProgramArguments</key>
      <array>
            <!-- YOUR *FULL, LITERAL* SCRIPT PATH HERE -->
          <string>/Users/Shared/Test.sh</string>
      </array>
      <key>RunAtLoad</key>
      <true/>
  </dict>
  </plist>
  

• The <!-- ... --> comments indicate the places to customize; you're free to choose a label, but it should be unique - ditto for the .plist filename; for simplicity, keep the label and the filename root the same.

• From Terminal.app, run the following:

  sudo chown root /Library/LaunchAgents/LoginScripts.Test.plist
  sudo launchctl load /Library/LaunchAgents/LoginScripts.Test.plist
  

• Note that, as a side effect, the script will execute right away. From that point on, the script will execute whenever ANY user logs on.

• It is not strictly necessary to run launchctl load -- since, by virtue of the file's location, it will be picked up automatically on next login -- but it's helpful for verifying that the file loads correctly.