OS X and iOS Kernel Programming

Process Management

A user typically has many applications installed on his or her computer. These are purely passive entities. The programs on disk contain data that is needed only when the program is run, consisting of the executable code and application data. When the user launches an application, the operating system loads the program's code and data into memory from disk and begins executing its code. A program being executed is known as a “process.” Unlike a program, a process is an active entity, and consists of a snapshot of the state of the program at a single instance during execution. This includes the program's code, the memory that the program has allocated, and the current state of its execution, such as the CPU instruction of the ...