(B17) Basic Linux part25 Process managment , Kill process, ps,kill

20220503 151900
process managment

ps -- report a snapshot of the current processes.
top -- live process


EXAMPLES
To see every process on the system using standard syntax:
ps -e
ps -ef
ps -eF
ps -ely

To see every process on the system using BSD syntax:
ps ax
ps axu

To print a process tree:
ps -ejH
ps axjf

To get info about threads:
ps -eLf
ps axms

To get security info:
ps -eo euser,ruser,suser,fuser,f,comm,label
ps axZ
ps -eM

To see every process running as root (real & effective ID) in user format:
ps -U root -u root u

To see every process with a user-defined format:
ps -eo pid,tid,class,rtprio,ni,pri,psr,pcpu,stat,wchan:14,comm
ps axo stat,euid,ruid,tty,tpgid,sess,pgrp,ppid,pid,pcpu,comm
ps -Ao pid,tt,user,fname,tmout,f,wchan
----------------------
ps -e

ps -ef

ps aux

ps -eo user,pid,ni,cmd



*every process has pid (process id)
-a process may has mutliple child process
-a process may has parent process
-a process must have pid and may have ppid(Parent process id)

kill process

kill pid

ps -e


--i open gedit

gedit &

ps -e
PID TTY TIME CMD
1 ? 00:00:04 systemd
1352 tty1 00:00:08 X
3036 pts/0 00:00:00 bash
3450 pts/3 00:00:00 bash
6288 pts/4 00:00:00 bash
6329 pts/4 00:00:00 gedit
6379 ? 00:00:00 sleep
6380 pts/4 00:00:00 ps

[root@B17linux1 ~]# kill 6329
[1]+ Terminated gedit
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[root@B17linux1 ~]# ps -ef
UID PID PPID C STIME TTY TIME CMD
root 1 0 0 10:48 ? 00:00:04 /usr/lib/systemd/systemd --switche
root 575 1 0 10:48 ? 00:00:00 /sbin/auditd
root 577 575 0 10:48 ? 00:00:00 /sbin/audispd
root 579 577 0 10:48 ? 00:00:00 /usr/sbin/sedispatch
root 796 1 0 10:48 ? 00:00:00 /usr/sbin/NetworkManager --no-daem
root 934 796 0 10:48 ? 00:00:00 /sbin/dhclient -d -q -sf /usr/libe
root 6444 6288 3 15:41 pts/4 00:00:00 gedit
root 6476 716 0 15:41 ? 00:00:00 sleep 60
student+ 6492 3152 0 15:43 pts/2 00:00:00 cat
root 6477 6288 0 15:41 pts/4 00:00:00 ps -ef
------------------------------------------
kill 6492

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ps aux
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 1 0.0 0.3 128376 7036 ? Ss 10:48 0:04 /usr/lib/systemd/s
root 6444 0.1 1.6 740900 30472 pts/4 Sl 15:41 0:00 gedit
root 6570 0.0 0.0 108052 352 ? S 15:47 0:00 sleep 60
root 6578 0.0 0.0 155448 1860 pts/4 R+ 15:48 0:00 ps aux

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customized

ps -eo user,pid,ni,cmd

[root@B17linux1 ~]# ps -eo user,pid,ni,cmd
USER PID NI CMD
root 1 0 /usr/lib/systemd/systemd --switched-root --system --deserialize
root 4 -20 [kworker/0:0H]
root 573 -20 [xprtiod]
root 575 -4 /sbin/auditd
root 577 -8 /sbin/audispd
root 579 -4 /usr/sbin/sedispatch
root 626 0 /usr/sbin/ModemManager
root 627 19 /usr/sbin/alsactl -s -n 19 -c -E ALSA_CONFIG_PATH=/etc/alsa/alsa
root 629 0 /usr/bin/abrt-watch-log -F BUG: WARNING: at WARNING: CPU: INFO:
rtkit 640 1 /usr/libexec/rtkit-daemon
root 796 0 /usr/sbin/NetworkManager --no-daemon
root 934 0 /sbin/dhclient -d -q -sf /usr/libexec/nm-dhcp-helper -pf /var/ru
root 6617 0 sleep 60
root 6631 0 ps -eo user,pid,ni,cmd
---------------------------------------------

[root@B17linux1 ~]# ps -eo user,pid,ni,cmd | grep gedit
root 6444 0 gedit
root 6764 0 grep --color=auto gedit

[root@B17linux1 ~]# kill 6444
[1]+ Terminated gedit

[root@B17linux1 ~]# ps -eo user,pid,ni,cmd | grep firefox
root 6795 0 /usr/lib64/firefox/firefox
root 7033 0 /usr/lib64/firefox/firefox -contentproc -childID 1 -isForBrowser -prefsLen 1 -prefMapSize 184074 -parentBuildID 20200707170725 -greomni /usr/lib64/firefox/omni.ja -appomni /usr/lib64/firefox/browser/omni.ja -appdir /usr/lib64/firefox/browser 6795 tab

[root@B17linux1 ~]# kill 6795
[root@B17linux1 ~]# ps -eo user,pid,ni,cmd | grep firefox
root 7246 0 grep --color=auto firefox
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kill process
-find process id
-kill pid

kill -l
[root@B17linux1 tmp]# kill -l
1) SIGHUP 9) SIGKILL 15) SIGTERM 20) SIGTSTP

kill pid and kill -15 pid --both are same -- terminate process

kill -9 pid -- kill process

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