This Bash script performs a controlled migration and cleanup process...

September 2, 2025 at 11:20 PM

/bin/bash -c # This script is loaded into system domain of lauhchd during postinstall script
# and runs as root. Be very careful what you do here as potential for damage is
# huge.  The script listens for commands on a named pipe and runs migration
# when it receives "run" command.

DESIRED_BUNDLE_PATH="/Applications/Microsoft Teams.app"
PREVIEW_BUNDLE_PATH="/Applications/Microsoft Teams (work preview).app"
WORK_OR_SCHOOL_BUNDLE_PATH="/Applications/Microsoft Teams (work or school).app"
MIGRATION_TOOL_PATH="$DESIRED_BUNDLE_PATH/Contents/Helpers/com.microsoft.teams2.migrationtool"
CONTROL_PIPE="/private/var/run/com.microsoft.teams2.migrationtool.ctl"
CONTROL_UNINSTALL_PIPE="/private/var/run/com.microsoft.teams2.migrationtool.t1removal.ctl"
CMD_RUN="run"
CMD_REMOVET1="removet1"
USER_NAME=$(/usr/bin/defaults read /Library/Preferences/com.apple.loginwindow lastUserName)
TEAMS_CLASSIC_BUNDLE_ID="com.microsoft.teams"
TEAMS_CLASSIC_PATH="/Applications/Microsoft Teams classic.app"

log() {
  echo "$(date +"%Y-%m-%dT%H:%M:%S%z") [$$] $1"
}

_AS_USER=$(/usr/bin/defaults read /Library/Preferences/com.apple.loginwindow lastUserName)
log "UI user: $_AS_USER"

run_as_ui_user() {
  /usr/bin/sudo -u "$_AS_USER" "$@"
}

stop_mau() {
  log "Killing MAU processes"
  /usr/bin/pkill -9 -x "Microsoft AutoUpdate"
  /usr/bin/pkill -9 -x "Microsoft Update Assistant"
  /usr/bin/pkill -9 -x "com.microsoft.autoupdate.helper"
}

migrate_bundle() {
  if [ ! -d "$1" ]; then
    log "$1 not found"
    return
  fi

  if [ -d "$DESIRED_BUNDLE_PATH" ]; then
    if /bin/rm -rf "$1"; then
      log "Removed $1"
    else
      log "Failed to remove $1"
    fi
  else
    if /bin/mv "$1" "$DESIRED_BUNDLE_PATH"; then
      log "Renamed $1 to $DESIRED_BUNDLE_PATH"
    else
      log "Failed to rename $1 to $DESIRED_BUNDLE_PATH"
    fi
  fi
}

remove_file()
{
  if [ ! -d "$1" ]; then
    log "$1 not found"
    return
  fi
  if [ -d "$1" ]; then
    if /usr/bin/sudo /bin/rm -rf "$1"; then
      log "Removed $1"
    else
      log "Failed to remove $1"
    fi
  fi
}

remove_classic_teams_traces()
{
  TEAMS_CLASSIC_APP=$1
  TEAMS_CLASSIC_CACHE="/Users/$USER_NAME/Library/Application Support/Microsoft/Teams"
  T1_TEAMS_UPDATER_DAEMON="$TEAMS_CLASSIC_APP/Contents/TeamsUpdaterDaemon.xpc/Contents/MacOS/TeamsUpdaterDaemon"
  T1_PROCESS_COUNT=$(ps aux | grep -v grep | grep -ci "$TEAMS_CLASSIC_APP")
  T1_UPDATER_DAEMON_COUNT=$(ps aux | grep -v grep | grep -ci "$T1_TEAMS_UPDATER_DAEMON")
 
  if [ "$T1_PROCESS_COUNT" -eq "0" ] || ([ "$T1_PROCESS_COUNT" -eq "1" ] && [ "$T1_UPDATER_DAEMON_COUNT" -eq "1" ]); then
    remove_file "$TEAMS_CLASSIC_APP"
    remove_file "$TEAMS_CLASSIC_CACHE"
  fi 
}

uninstall_classic_teams() {
  if [ -d "$TEAMS_CLASSIC_PATH" ]; then
    T1_BUNDLE_ID=$(/usr/bin/defaults read "$TEAMS_CLASSIC_PATH/Contents/Info" CFBundleIdentifier)
    if [ "$T1_BUNDLE_ID" == "$TEAMS_CLASSIC_BUNDLE_ID" ]; then
      remove_classic_teams_traces "$TEAMS_CLASSIC_PATH"
    fi
  else
    TEAMS_CLASSIC_PATH=$(mdfind "kMDItemCFBundleIdentifier == '$TEAMS_CLASSIC_BUNDLE_ID'" -onlyin /Applications)
    TEAMS_CLASSIC_APP_COUNT=$(mdfind "kMDItemCFBundleIdentifier == '$TEAMS_CLASSIC_BUNDLE_ID'" -onlyin /Applications -count)
    if [ ! -z "$TEAMS_CLASSIC_PATH" ] && [ "$TEAMS_CLASSIC_APP_COUNT" == "1" ]; then
      remove_classic_teams_traces "$TEAMS_CLASSIC_PATH"
    else
      log "Classic Teams not found"
    fi
  fi
}

check_app_exists() {
  APP_BUNDLE_ID=$1
  APP_PATH=$(mdfind "kMDItemCFBundleIdentifier == '$APP_BUNDLE_ID'" -onlyin /Applications)
  APP_COUNT=$(mdfind "kMDItemCFBundleIdentifier == '$APP_BUNDLE_ID'" -onlyin /Applications -count)
  if [ ! -z "$APP_PATH" ] && [ "$APP_COUNT" == "1" ]; then
    return 0
  else
    return 1
  fi
}

run_migration() {
  log "Runnig migration"

  if [ -d "$PREVIEW_BUNDLE_PATH" ] && [ -d "$WORK_OR_SCHOOL_BUNDLE_PATH" ]; then
    log "There are both $PREVIEW_BUNDLE_PATH and $WORK_OR_SCHOOL_BUNDLE_PATH, not sure which one to rename"
    return
  fi

  migrate_bundle "$PREVIEW_BUNDLE_PATH"
  migrate_bundle "$WORK_OR_SCHOOL_BUNDLE_PATH"
}

fix_dock_icon() {
  if [ -x "$MIGRATION_TOOL_PATH" ]; then
    log "Running migration tool to fix dock icon"
    run_as_ui_user "$MIGRATION_TOOL_PATH" --fix-dock-icon
  else
    log "Migration tool not found at $MIGRATION_TOOL_PATH"
  fi
}

# should be in-sync with the code in src/mac/scripts/installer/postinstall
MAU_BUNDLE_ID="com.microsoft.autoupdate2"
MAU_APP_PATH="/Library/Application Support/Microsoft/MAU2.0/Microsoft AutoUpdate.app"
MAU_SYSTEM_PREFS_PATH="/Library/Preferences/${MAU_BUNDLE_ID}"
MAU_APPLICATION_ID="TEAMS21"
MAU_LCID="1033"
MAU_TEAMS_DICT="{ 'Application ID' = '${MAU_APPLICATION_ID}'; LCID = '${MAU_LCID}';}"

register_to_mau() {
  if [ ! -d "${MAU_APP_PATH}" ]; then
    log "MAU is not installed, skipping registration."
    return
  fi

  local REGISTERED_USER_APPLICATION_ID=$(/usr/libexec/PlistBuddy -c "Print :Applications:'${DESIRED_BUNDLE_PATH}':'Application ID'" ~/Library/Preferences/${MAU_BUNDLE_ID}.plist 2> /dev/null)
  if [ "${REGISTERED_USER_APPLICATION_ID}" = "${MAU_APPLICATION_ID}" ]; then
    log "Teams is already registered to MAU (user)"
  else
    if run_as_ui_user /usr/bin/defaults write ${MAU_BUNDLE_ID} Applications -dict-add "${DESIRED_BUNDLE_PATH}" "${MAU_TEAMS_DICT}"; then
      log "Teams has been registered to MAU (user)"
    else
      log "Failed to register Teams to MAU (user)"
    fi
  fi

  local REGISTERED_SYSTEM_APPLICATION_ID=$(/usr/libexec/PlistBuddy -c "Print :ApplicationsSystem:'${DESIRED_BUNDLE_PATH}':'Application ID'" ${MAU_SYSTEM_PREFS_PATH}.plist 2> /dev/null)
  if [ "${REGISTERED_SYSTEM_APPLICATION_ID}" = "${MAU_APPLICATION_ID}" ]; then
    log "Teams is already registered to MAU (system)"
  else
    if /usr/bin/defaults write ${MAU_SYSTEM_PREFS_PATH} ApplicationsSystem -dict-add "${DESIRED_BUNDLE_PATH}" "${MAU_TEAMS_DICT}"; then
      log "Teams has been registered to MAU (system)"
    else
      log "Failed to register Teams to MAU (system)"
    fi
  fi
}

start_app() {
  log "Starting $DESIRED_BUNDLE_PATH as $_AS_USER"
  run_as_ui_user /usr/bin/open "$DESIRED_BUNDLE_PATH"
}

remove_control_pipe() {
  if [ -e "$1" ]; then
    log "Removing existing pipe at $1"
    /bin/rm -f "$1"
  fi
}

clean_cache() {
  log "Cleaning up any stale cache"

  remove_control_pipe "$CONTROL_PIPE"
  remove_control_pipe "$CONTROL_UNINSTALL_PIPE"
}

make_control_pipe() {
  remove_control_pipe "$1"

  /usr/bin/mkfifo "$1"

  if [ -p "$1" ]; then
    /bin/chmod 0666 "$1"
    log "Created a pipe at $1"
  else
    log "Failed to create a pipe at $1"
    exit 1
  fi
}


listen_for_command_on_rename_pipe() {
  if [ -e "$CONTROL_PIPE" ]; then
    log "Listening for commands on $CONTROL_PIPE"

    while true; do
      if read -r RECV_CMD < "$CONTROL_PIPE"; then
        log "Received command: $RECV_CMD on $CONTROL_PIPE"

        if [ "$RECV_CMD" = "$CMD_RUN" ]; then
          stop_mau
          sleep 1 # for a good measure
          run_migration
          fix_dock_icon
          register_to_mau
          start_app
        fi
        break
      elif [ $? -ne 0 ]; then
        log "Interrupted system call on $CONTROL_PIPE, retrying..."
      fi
    done
  fi
}

listen_for_command_on_uinstall_pipe() {
  if [ -e "$CONTROL_UNINSTALL_PIPE" ]; then
    log "Listening for commands on $CONTROL_UNINSTALL_PIPE"

    while true; do
      if read -r RECV_CMD < "$CONTROL_UNINSTALL_PIPE"; then
        log "Received command: $RECV_CMD on $CONTROL_UNINSTALL_PIPE"

        if [ "$RECV_CMD" = "$CMD_REMOVET1" ]; then
          uninstall_classic_teams
        fi
        break
      elif [ $? -ne 0 ]; then
        log "Interrupted system call on $CONTROL_UNINSTALL_PIPE, retrying..."
      fi
    done

  fi
}

exit_cleanup() {
  local exit_status=$?
  if [ $exit_status -eq 0 ]; then
    log "Successfully completed script."
  else
    log "Script exited with non-zero status: $exit_status."
  fi

  clean_cache

  log "Unloading migration tool"
  /bin/launchctl bootout system/com.microsoft.teams2.migrationtool
  # We're in exit trap but command above will cause launchd to kill us
  log "This should not be reached"
}

trap exit_cleanup EXIT

clean_cache # clean up any stale state

# create control pipe for rename only if legacy T2.1 app is detected
if [ -d "$PREVIEW_BUNDLE_PATH" ] || [ -d "$WORK_OR_SCHOOL_BUNDLE_PATH" ]; then
  make_control_pipe "$CONTROL_PIPE"
  listen_for_command_on_rename_pipe
fi

# create control pipe for T1 removal only if Classic Teams app is detected
check_app_exists "$TEAMS_CLASSIC_BUNDLE_ID"
T1_EXISTS=$?
if [ $T1_EXISTS -eq 0 ]; then
  make_control_pipe "$CONTROL_UNINSTALL_PIPE"
  listen_for_command_on_uinstall_pipe
fi

check_app_exists "$TEAMS_CLASSIC_BUNDLE_ID"
T1_EXISTS=$?
if [ ! -d "$PREVIEW_BUNDLE_PATH" ] && [ ! -d "$WORK_OR_SCHOOL_BUNDLE_PATH" ] && [ $T1_EXISTS -eq 1 ]; then
  # If legacy T2.1 app and T1 app are not detected, unload migration tool as it is not needed anymore
  log "Migration tool is no longer needed. Exiting."
  exit 0
fi

This Bash script performs a controlled migration and cleanup process for Microsoft Teams applications on macOS. It is run as the root user after installation and is heavily focused on managing different versions of Microsoft Teams apps and performing migration-related tasks. Below is a breakdown of what the script does:

1. Definition of Key Paths and Variables

Defines paths for different Microsoft Teams application bundles (e.g., classic and preview versions).
Defines control mechanisms using named pipes (CONTROL_PIPE and CONTROL_UNINSTALL_PIPE) to listen for specific commands (run and removet1).
Identifies the currently logged-in user using macOS preferences (/Library/Preferences/com.apple.loginwindow lastUserName).

2. Log Helper Function

Logs timestamped messages (log function) to track the flow and state of operations.

3. Helper Functions

run_as_ui_user: Executes commands as the logged-in user.
stop_mau: Terminates Microsoft AutoUpdate (MAU)-related processes forcibly.
migrate_bundle: Renames or removes an existing app bundle for newer versions.
remove_file & remove_classic_teams_traces: Removes specific app traces and caches, such as Classic Teams files.
uninstall_classic_teams: Checks and removes the "classic" Teams version, including its traces.
check_app_exists: Checks for the presence of a specific application bundle by identifier.
run_migration: Handles the migration of legacy Teams bundles to the desired bundle path.
fix_dock_icon: Runs a migration tool to fix the app's dock icon after migration.
register_to_mau: Registers the migrated Teams app with Microsoft AutoUpdate (MAU).
start_app: Opens the newly migrated Teams app for the user.
remove_control_pipe & make_control_pipe: Manages the creation and cleanup of named pipes for inter-process communication.

4. Main Processes

Cleanup on Start:
- Removes any stale state (e.g., existing named pipes).
Migration Logic:
- If legacy Teams "work preview" or "work or school" bundles are detected, sets up a named pipe (CONTROL_PIPE) to listen for the run command and initiates migration.
Uninstallation Logic:
- If the classic version of Teams is detected, sets up another named pipe (CONTROL_UNINSTALL_PIPE) to listen for the removet1 command and removes the classic app and its traces.
Exit Clean-Up:
- Performs cleanup upon script exit, such as removing named pipes and unloading the migration tool.

5. Listening for Commands

listen_for_command_on_rename_pipe:
- Waits for the run command on the CONTROL_PIPE, triggering Teams migration, fixing the dock icon, registering the app with MAU, and starting the app.
listen_for_command_on_uninstall_pipe:
- Waits for the removet1 command on the CONTROL_UNINSTALL_PIPE, triggering the removal of the Classic Teams app.

6. Exit Behavior

If no legacy or classic Teams apps are present, the script unloads the migration tool and exits because it's no longer needed.

In Summary

The script aims to:

Migrate users from older versions of Microsoft Teams (Work Preview / Classic) to the new desired bundle app.
Optionally remove legacy traces of the Classic Teams app.
Ensure the migrated Teams app is properly registered with Microsoft AutoUpdate and functions as expected.
Manage communication with the migration tool using named pipes and react to specific commands (run and removet1).
Safeguard the system by cleaning up stale state and unloading the migration tool when no longer needed.

The script operates cautiously because it is executed as root and modifies system-critical application paths, which carries a high potential for unintended consequences if misused or containing errors.

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