Cocoa Programming for OS X: The Big Nerd Ranch Guide

35 NSTask

Each application that you have created is a bundle, a directory which OS X displays to the user as a single file. Somewhere down in that directory is an executable file. To run an executable on a Unix machine, like your Mac, a process is forked and the new process executes the code in that file. Many executables are command-line tools, and some are quite handy. In this chapter, you will learn how to run a command-line tool from your Cocoa application using NSTask.

NSTask is an easy-to-use wrapper for the Unix functions fork() and exec(). You give NSTask a path to an executable and launch it. Many processes read data from standard-in and write to standard-out and standard-error. Your application can use NSTask to attach ...