How to catch error when setting launchpath in NSTask

Question

I am trying to run a commandline tool using swift 2 on a mac (10.10):

let task = NSTask()
task.launchPath = \"/path/to/wrong/binary\"
task.launch()

// NSPip         


        

Answer 1

unfortunately, there is no chance to catch runtime exceptions. with try / catch you can recovery from trowing error, not from runtime exception. you can create you own exception handler, but you are still not able to recover from it. try to lunch from NSTask some common shell with command as a parameter and next use a pipe to return os errors to you own code.

import Foundation

let task = Process()
let pipe = Pipe()
task.launchPath = "/bin/bash"
task.arguments = ["-c","unknown"]
task.standardOutput = pipe
task.launch()
let handle = pipe.fileHandleForReading
let data = handle.readDataToEndOfFile()
let dataString = String(data: data, encoding: .utf8)
print(dataString ?? "")

will print

/bin/bash: unknown: command not found