Solution for Ch 35 Challenge: .tar and .tgz Files

Cocoa Programming for OS X (5th Edition) 35. NSTask
1

Create 2 Document Types

Name: Tar archive
Identifier: public.tar-archive
Class: $(PRODUCT_MODULE_NAME).Document
Role: Viewer

Name: Gzip tar archive
Identifier: org.gnu.gnu-zip-tar-archive
Class: $(PRODUCT_MODULE_NAME).Document
Role: Viewer

Update read(from:ofType:)

override func read(from url: URL, ofType typeName: String) throws {
  // Which file are we getting the zipinfo for?
  let filename = url.path
  
  // Prepare a task object
  let task = Process()    
  switch url.pathExtension {
  case "tar":
    task.launchPath = "/usr/bin/tar"
    task.arguments = ["tf", filename]
  case "tgz":
    task.launchPath = "/usr/bin/tar"
    task.arguments = ["tzf", filename]
  default:
    task.launchPath = "/usr/bin/zipinfo"
    task.arguments = ["-1", filename]
  }
. . .