5 Linux Process States Explained

There are a total of five different states for Linux processes:

1. “Running status: The process is either running or waiting for CPU resources to execute.”
2. Waiting state: A process is waiting for a certain event to occur, such as receiving input, waiting for an IO operation to complete, or waiting for another process to release resources.
3. Stopped state: the process is paused from executing, usually due to receiving a stop signal (like CTRL+Z) or being paused by a debugging tool.
4. Zombie state: The process has terminated, but its parent process has not yet called the wait() system call to receive the exit status of the process.
5. Zombie Stopped: The process has terminated execution, but its parent process has not yet called the wait() system call to retrieve the exit status of the process, and the process was also in a stopped state before it was paused.

It should be noted that zombie processes are not a normal process state; instead, they indicate that the process resources have not been fully released.