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I wish to use mp3blaster (installed through MacPorts) via Finder. I want to double-click an mp3 file and get it opened in mp3blaster. But I haven't been able to do so. I created an app and, in another try, a service in Automator, using the following script:

/opt/local/bin/mp3blaster $1

Any ideas?

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You should be able to get info on your .mp3 file and change the associated app.

Go to cmd-i of your app, click the drop-down of "Open with:" .. Select other and navigate to your directory. You will have to select Enable : All Applications to be able to click on the mp3blaster app.

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The problem is that mp3blaster is not an app but a bin. So I cannot do what you suggest. – NVaughan Nov 19 '12 at 22:49
I think you might have to create an apple script and then have the files associated to the apple script. – Mark Cohen Nov 20 '12 at 0:17
Thanks. I tried to, unsuccessfully. Could you please tip me on that? – NVaughan Nov 20 '12 at 15:08

Start Automator, create a workflow with a Run AppleScript action and save it as an application.

enter image description here

Then select any mp3 file, type Cmd-I and change the default application to the application saved before.

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Thanks, @patrix. But it doesn't work. Same error message. (Of course, if I run /opt/local/bin/mp3blaster from a bash shell it works.) – NVaughan Nov 20 '12 at 19:30
What happens if you run it inside Automator and look at "Results" afterwards? – patrix Nov 20 '12 at 21:45
See here: – NVaughan Nov 20 '12 at 22:23
Ah, of course, you can't run interactive commands with a "Run Shell Script" action. – patrix Nov 21 '12 at 5:05

Use $@ to refer to a file being passed to a shell script in Automator:

/opt/local/bin/mp3blaster $@


/opt/local/bin/mp3blaster "$@"
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I get the error, "The action “Run Shell Script” encountered an error." – NVaughan Nov 20 '12 at 15:47

Finally managed how to do it using AppleScript instead of bash. (I followed this example: Firing up Terminal from an Automator Workflow?)

on run {input, parameters}
    tell application "Terminal"
        if (the (count of the window) = 0) or ¬
            (the busy of window 1 = true) then
            tell application "System Events"
                keystroke "n" using command down
            end tell
        end if
        do script "/opt/local/bin/mp3blaster \"" & (POSIX path of ¬
            (input as string)) & "\"" in window 1
    end tell
    return input
end run
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However, this only works for single files taken as input. How could I alter the script to parse multiple files? – NVaughan Nov 22 '12 at 2:18

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