Print a process tree using ps

from https://www.cyberciti.biz/faq/show-all-running-processes-in-linux/

Linux commands show all running processes

Apart from ps command, you can also use the following commands to display info about processes on Linux operating systems:

1. top command : Display and update sorted information about Linux processes.
2. atop command : Advanced System & Process Monitor for Linux.
3. htop command : Interactive process viewer in Linux.
4. pgrep command : Look up or signal processes based on name and other attributes.
5. pstree command : Display a tree of processes.

# ps -ejH
# ps axjf
Sample outputs:

How to display a tree of processes

The pstree command shows running processes as a tree. The tree is rooted at either pid or init if pid is omitted. If a user name is specified, all process trees rooted at processes owned by that user are shown.
$ pstree
Sample outputs:

Linux running processes with top command

The top program provides a dynamic real-time view of a running system. Type the top at command prompt:
# top
Sample outputs:

See process run by user vivek

Select by process by effective user ID (EUID) or name by passing username such as vivek:
# ps -u vivek

How to list process with the ps command

Type the following ps command to display all running process:
# ps -aux | less
OR
# ps aux | less
Where,

• A : Select all processes
• u : Select all processes on a terminal, including those of other users
• x : Select processes without controlling ttys