Process and Process Attributes in Operating System:
Definition and Explanation:
An operating system executes a variety of programs depending on the system. In batch system, a program is called job. In time-shared system, it might be called a user program or task. Normally, the terms job and process are used almost interchangeably.
A more precise definition of the term process is that "A process is a program in execution". A process has a starting and ending place. It must execute and progress sequentially. At most, one instruction may be performed on behalf of the process at any given time. A process is controlled and scheduled by operating system.
Process Attributes:
A process has the following attributes:
- A program counter is used to keep track of the address of the next instruction to be executed.
- A stack is used to store temporary data for the process.
- A data section is used that may contain global variables.
A program is a passive entity. It specifies the logic of data manipulation and I/O actions. A program does not perform the actions itself. It has to be executed to realize the action. A process is an active entity. It performs the actions specified in the program.
