Introduction
The Linux command pstree is a useful tool for displaying the hierarchical relationship between processes running on a Linux system. It provides a visual representation of the process tree, showing the parent-child relationship between processes. It can be used to identify which processes are running, which are related to each other, and which are consuming the most resources. It can also be used to identify processes that are stuck in an infinite loop or are otherwise misbehaving.
Examples
The pstree command is used to display a tree of processes running on a Linux system. It shows the hierarchical relationship between processes and their parent processes.
Syntax:
pstree [options] [PID]
Options:
-a: Show command line arguments of processes
-A: Show command line arguments of processes in ASCII art
-c: Show process IDs
-g: Show process group IDs
-G: Show process group IDs in ASCII art
-l: Show long format
-n: Show numeric PIDs
-p: Show process IDs in parentheses
-u: Show user names
Example:
To display a tree of processes running on the system, use the following command:
$ pstree
Output:
init─┬─NetworkManager─┬─dhclient
│ └─dnsmasq
├─acpid
├─agetty
├─atd
├─cron
├─dbus-daemon
├─getty
├─irqbalance
├─kauditd
├─kblockd
├─kdm
├─kondemand
├─ksplash
├─kthreadd
├─login
├─mingetty
├─nmbd
├─ntpd
├─portmap
├─rpc.statd
├─rpcbind
├─smbd
├─sshd
├─udevd
├─winbindd
├─xfs
└─ypbind
Understanding the pstree Linux Command
The pstree command is a useful tool for Linux users to view the hierarchical structure of processes running on the system. It displays the parent-child relationship between processes in a tree-like format, making it easier to understand the process structure. This command is especially useful for debugging and troubleshooting, as it can help identify the source of a problem.
The pstree command is part of the procps package, which is installed by default on most Linux distributions. To use the command, simply type pstree in the terminal. This will display a tree of all the processes running on the system. The tree will show the parent-child relationship between processes, with the parent process at the top and the child processes below it.
The pstree command can also be used to display the processes of a specific user. To do this, use the -u option followed by the username. For example, pstree -u john will display the processes of the user john. Additionally, the -p option can be used to display the process IDs of each process in the tree.
The pstree command is a powerful tool for understanding the process structure of a Linux system. It can be used to identify the source of a problem, as well as to monitor the system for any suspicious activity. With its tree-like format, it makes it easy to understand the parent-child relationship between processes.
