Show only running processes and specific processes
●View running processes
The ps command basically shows all the processes that are not completed, so it will also show the processes that are stopped.
To show only running processes, run the ps command with the option "-r".
|root@Lion:~# ps -axr
PID TTY STAT TIME COMMAND
30144 pts/0 R+ 0:00 ps -axr
Information to be displayed
PID：A number that is automatically assigned to each process
TTY：Control terminal running the process
T：Stopping or tracing
D：Dormant and uninterruptible.
Z：zombie（Not deleted, but suspended）
W：swapped out（No resident pages）
N：positive nice value
TIME：CPU consumption time
●Show only the status of a specific process
The ps command normally displays all processes, but it can also be used to display specific processes.
To do so, run the ps command with the option "-C".
Also, if you know the PID (Process ID), you can specify the PID as an argument to display only the status of a specific process.。
|root@Lion:~# ps -lC crond←Show only "crond" processes
F S UID PID PPID C PRI NI ADDR SZ WCHAN TTY TIME CMD
5 S 0 1770 1 0 78 0 - 1323 - ? 00:00:00 crond