How can I execute a shell script in Swift?

Question

I am creating a macOS app with Swift that needs to download and run a shell script. I have been able to download the script with curl, but I can't run it. I am using a function from this answer to run other commands. When I use the App Sandbox in Xcode, I get the error /bin/bash: ./file.sh: Permission denied. When I try changing file permissions, I get the error chmod: Unable to change file mode on file.sh: Operation not permitted.

Here is my code:

func shell(_ command: String) -> String {
    let task = Process()
    task.launchPath = "/bin/bash"
    task.arguments = ["-c", command]

    let pipe = Pipe()
    task.standardOutput = pipe
    task.launch()

    let data = pipe.fileHandleForReading.readDataToEndOfFile()
    let output: String = NSString(data: data, encoding: String.Encoding.utf8.rawValue)! as String

    return output
}

shell("curl https://www.example.com/file.sh -o file.sh")
shell("./file.sh")

Output:

% Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                               Dload  Upload   Total   Spent    Left  Speed

  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0
  1 16.0M    1  224k    0     0   231k      0  0:01:11 --:--:--  0:01:11  231k
 47 16.0M   47 7808k    0     0  4064k      0  0:00:04  0:00:01  0:00:03 4062k
100 16.0M  100 16.0M    0     0  6037k      0  0:00:02  0:00:02 --:--:-- 6037k


/bin/bash: ./file.sh: Permission denied

You have to set execute permission to run the script: `chmod +x file.sh` — Yoda, Oct 04 '19 at 00:18
Check the permissions of these directories:- `/bin /lib /` Change them to `755` — Yoda, Oct 04 '19 at 00:31
@Yoda I get this error: `chmod: Unable to change file mode on /: Operation not permitted` — Ryland Goldman, Oct 04 '19 at 18:25
You cannot run a shell script with `Process` if the app is sandboxed. — vadian, Oct 04 '19 at 18:33
@vadian I am able to run commands, like `curl.` Can I just not run a script? — Ryland Goldman, Oct 04 '19 at 18:36
@vadian And is there any other way without using `Process` that I could run a shell script when the app is sandboxed? — Ryland Goldman, Oct 04 '19 at 18:53
Only if the user puts the script in Application Scripts and runs the script with NSUserUnixTask — vadian, Oct 04 '19 at 18:57
@vadian How do I use NSUserUnixTask? Also, you said the user has to put the script there. Could the application do it? Or am I misunderstanding something? — Ryland Goldman, Oct 04 '19 at 22:05
Please read the [documentation](https://developer.apple.com/documentation/foundation/nsuserunixtask) — vadian, Oct 05 '19 at 04:56

How can I execute a shell script in Swift?

0 Answers0