MacOS – AppleScript vs. Bash script

applescriptbashmacos

I'm a long-time Windows "power user" and developer who has recently decided to move over to Mac OS X.

On OS X Lion and indeed previous versions there seem to be two main options for scripting and automation in OS X: AppleScript and Bash script. The latter is of course a direct consequence of OS X using the Unix "bash" shell, while the former is Apple's own innovation. The syntaxes are clearly very different, with AppleScript having a pseudo-natural-language style.

My question is, are AppleScript and Bash script commonly used (indeed, should they be used) for disparate tasks and purposes on OS X. I am vaguely cognizant of the vast array of tasks I can accomplish with Bash script, though of course the code for some more advanced ones can quickly become convoluted. Do these two languages have overlapping or near-identical usage cases, despite Apple's later invention of AppleScript — or are they intended to be used with different scenarios in mind? A high-level overview as well as some specific examples would be appreciated.

Best Answer

Both shell- and AppleScripts can be used just about anywhere either is appropriate.

AppleScripts work better when talking to apps and user-level system facilities. (For instance, you can say tell app "iTunes" to play and it will, or tell app "Finder" to open the first file of the second window.)

Shell scripts (you referred to bash) work better when talking to low-level system objects and Unixy stuff.

They're both interoperable: you can call a shell command from AppleScript with do shell script "command here" and you can call AppleScript code from the shell with osascript -e "AppleScript". Further, there's quite a bit of overlap between the two (especially when it comes to file system operations).

There are certainly more resources for learning shell scripting online than AppleScript and it doesn't help that AppleScript has a reputation for being a "read-only" language (i.e., harder to write than read).

In any case, the most modern way to do scripting is with Automator, where you can use either shell- or AppleScripting (or both) along with pre-built modules from various apps you have installed.

Related Solutions

Applescript dialog, Bash alias/function

You can use the run handler to pass arguments:

dialog() {
    osascript -e 'on run args
    try
    tell app "SystemUIServer" to display dialog (item 1 of args)
    end
    activate app (path to frontmost application as text)
    end' "$1"
}

If you want to call it like dialog a b (instead of dialog 'a b'), change $1 to $*.

System Events quits automatically when it is not used, and there is a small delay when it is opened, so telling it to display the dialog would sometimes be slower.

Without the try block there would be an error if the user presses a cancel button. Without activate the previously focused window wouldn't get focus back when the dialog is closed.

You can use something like this to display text dialogs:

answer=$(osascript -e 'try
tell app "SystemUIServer"
set answer to text returned of (display dialog "" default answer "")
end
end
activate app (path to frontmost application as text)
answer' | tr '\r' ' ')
[ -z "$answer" ] && exit

MacOS – Run AppleScript from bash script

The argument for osascript -e can contain newlines:

osascript -e 'set x to "a"
say x'

You can also specify multiple -e arguments:

osascript -e 'set x to "a"' -e 'say x'

Or if you use a heredoc, bash interprets three characters (\, $, and `) between <<END and END but no characters between <<'END' and END.

osascript <<'END'
set x to "a"
say x
END

Edit:

Since osascript can operate with a heredoc (ie take input from /dev/stdin) then one can just write the script as a whole file and prepend with the correct shebang line:

#!/usr/bin/env osascript

set x to "a"
say x

This also allows you to save your apple script as a actual program in ~/Applications/.app using the following procedure (changing for your script's name):

mkdir -p ~/Applications/<APP_NAME>.app/Contents/MacOS
touch ~/Applications/<APP_NAME>.app/Contents/MacOS/<APP_NAME>
open -A TextEdit ~/Applications/<APP_NAME>.app/Contents/MacOS/<APP_NAME>

Ensure that both the script file in .../MacOS/ and the matches

Best Answer

Related Solutions

Applescript dialog, Bash alias/function

MacOS – Run AppleScript from bash script

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