How to check in AppleScript if an app is running, without launching it - via osascript utility

Question

Consider the following AppleScript:

on is_running(appName)
    tell application \"System Events\" to (name of processes) contains appName
end is_running

set         


        

Answer 1

All the previously made answers suffer from the same issue, though:

They look for the app by its name. However, the user may rename the app, and then the script will believe the app does not run, when in fact it does.

To properly check for a running app, it should be found by its bundle ID, which the user cannot change.

The bundle ID can be inquired with this command, for instance, when the app is already running:

tell application "System Events"
    get bundle identifier of application process "Safari"
end tell

Or like this for any installed app:

get id of application "Safari"

To check whether an app with a particular bundle ID is running, use this code:

tell application "System Events"
    set ids to bundle identifier of every application process
    if ids contains "com.apple.safari" then
        return "Running"
    else
        return "Not running"
    end if
end tell

Furthermore, here's an example to check if an app is running, then quit it, then relaunch it, ensuring that the very same app is relaunched that was running before, and not some other copy that may also exist:

set bundleID to "com.apple.safari"
set apps to runningApps(bundleID)
set appCount to length of apps
if appCount is not 0 then
    quit application id bundleID
    repeat while length of runningApps(bundleID) = appCount
        -- wait for the app to quit
    end repeat
    open first item of apps
end if

on runningApps(bundleID)
    -- The try block is to catch the rare case of having more than one
    -- copy of an app running at the same time. Unfortunately, in that
    -- case this code will not run as expected, because we don't get the
    -- correct list of multiple items back then. But at least the script
    -- will not crash from it but handle it gracefully.
    tell application "System Events"
        try
            return application file of (every application process whose bundle identifier = bundleID)
        end try
    end tell
    return {}
end runningApps