Basic CLI (Command Line Interface) Tools Pt. 2
Posted 06-19-2013 at 06:35 PM by Nbiser
In Pt. 1, I covered basic command line tools and commands. I will continue that theme here, in Pt. 2.
First I would like to cover the command ps. This command is used to view processes. In its basic form without any options its output looks like this:
Here it only shows the most basic processes that are running on the system. PID stands for the process ID, time shows how long the process has been running, CMD shows the command used to launch the process while TTY is the code used to identify the terminal.
I will now show you a more advanced (and more useful) form of ps. The ps -u user command.
The option -u makes the terminal show all of the processes that that specified user is running.
Another option that can be used is:
This shows all of the options running on the system. (Please note: I shortened the output of ps -e because it is way to long to post.)
And finally, ps -u U user:
This option shows more information. I can't go into this in depth, but the %CPU and %MEM columns show the amount of CPU and RAM that is being used. The last tool that I will cover for looking at processes is the top command. It shows a live view of the processes being run:
(please note: the output was shortened)
Top is probably better than ps because it shows the processes that are being run in real time, thus giving a better idea of the processes that are using up the most RAM and CPU time.
We can now move on to ending processes.
If you need to end a process use ps or top to determine the PID, you then type this command:
This will end the process immediately.
We now come to redirecting text. Lets say that use use the command ps -e, but the output is too long to display on the screen. To get around this problem you need to type:
This will redirect the output a .txt file.
To create a directory you need to type
This will make the specified directory.
Finally, we come to removing files and directories. Lets say that you have a file named ezyremove.txt, and you wish to remove it. To do so you should tyep:
This will permanently erase your file: you won't be able to recover it.
To erase a directory your need to type
which will completely erase the directory and its contents.
First I would like to cover the command ps. This command is used to view processes. In its basic form without any options its output looks like this:
Code:
nbiser@linux-vqbm:~> ps PID TTY TIME CMD 14933 pts/1 00:00:00 ps 17047 pts/1 00:00:00 bash
I will now show you a more advanced (and more useful) form of ps. The ps -u user command.
Code:
nbiser@linux-vqbm:~> ps -u nbiser PID TTY TIME CMD 1543 ? 00:00:00 startkde 2703 ? 00:00:00 dbus-launch 2730 ? 00:00:00 dbus-daemon 2906 ? 00:00:00 kdeinit4 3431 ? 00:00:00 klauncher 3463 ? 00:00:02 kded4 3710 ? 00:00:00 kglobalaccel 3817 ? 00:00:00 kwalletd 3835 ? 00:00:00 kactivitymanage 3865 ? 00:00:00 kwrapper4 3879 ? 00:00:00 ksmserver 3954 ? 00:00:40 kwin 4601 ? 00:00:13 plasma-desktop 4621 ? 00:00:01 knotify4 5194 ? 00:00:00 kuiserver 5473 ? 00:00:00 kaccess 5480 ? 00:00:00 nepomukserver 5483 ? 00:00:32 vmtoolsd 5486 ? 00:00:00 nepomukservices 5488 ? 00:00:02 krunner 5496 ? 00:00:00 polkit-kde-auth 5497 ? 00:00:00 nepomukcontroll 5500 ? 00:00:00 klipper 5502 ? 00:00:00 kmix 5508 ? 00:00:01 pulseaudio 5545 ? 00:00:00 akonadi_control 5548 ? 00:00:00 akonadiserver 5550 ? 00:00:06 mysqld 5590 ? 00:00:00 akonadi_agent_l 5591 ? 00:00:00 akonadi_agent_l 5592 ? 00:00:00 akonadi_agent_l 5593 ? 00:00:00 akonadi_agent_l 5594 ? 00:00:00 akonadi_maildis 5595 ? 00:00:00 akonadi_mailfil 5596 ? 00:00:00 akonadi_nepomuk 5598 ? 00:00:07 virtuoso-t 5658 ? 00:00:00 kio_http_cache_ 5668 ? 00:00:00 nepomukservices 5669 ? 00:00:00 nepomukservices 5670 ? 00:00:00 nepomukservices 6271 ? 00:00:00 apper-sentinel 11415 ? 00:00:00 krandrtray 14090 ? 00:01:01 firefox 14905 ? 00:00:00 kmozillahelper 15237 pts/1 00:00:00 ps 17014 ? 00:00:00 gconfd-2 17045 ? 00:00:03 konsole 17047 pts/1 00:00:00 bash
Another option that can be used is:
Code:
nbiser@linux-vqbm:~> ps -e
PID TTY TIME CMD
1 ? 00:00:02 systemd
2 ? 00:00:00 kthreadd
3 ? 00:00:00 ksoftirqd/0
6 ? 00:00:00 migration/0
7 ? 00:00:18 rcuc/0
8 ? 00:00:00 rcun/0
9 ? 00:00:00 rcub/0
10 ? 00:00:00 rcun/1
11 ? 00:00:00 rcub/1
12 ? 00:00:02 watchdog/0
13 ? 00:00:00 cpuset
14 ? 00:00:00 khelper
And finally, ps -u U user:
Code:
nbiser@linux-vqbm:~> ps u U nbiser USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND nbiser 1543 0.0 0.1 13000 1480 ? Ss 12:06 0:00 /bin/sh /usr/bin/startkde nbiser 2703 0.0 0.0 22236 556 ? S 12:06 0:00 dbus-launch --sh-syntax --exit-with-session nbiser 2730 0.0 0.1 29592 2036 ? Ss 12:06 0:00 /bin/dbus-daemon --fork --print-pid 5 --print-address 7 --session nbiser 2906 0.0 1.8 312604 18784 ? Ss 12:06 0:00 kdeinit4: kdeinit4 Running... nbiser 3431 0.0 0.6 316288 7008 ? S 12:06 0:00 kdeinit4: klauncher [kdeinit] --fd=9 nbiser 3463 0.0 2.3 810504 23788 ? Sl 12:06 0:02 kdeinit4: kded4 [kdeinit] nbiser 3710 0.0 1.1 392940 11576 ? S 12:06 0:00 kdeinit4: kglobalaccel [kdeinit] nbiser 3817 0.0 1.0 396192 10520 ? S 12:06 0:00 kdeinit4: kwalletd [kdeinit] nbiser 3835 0.0 1.5 251164 15888 ? S 12:06 0:00 /usr/bin/kactivitymanagerd nbiser 3865 0.0 0.0 4184 352 ? S 12:06 0:00 kwrapper4 ksmserver nbiser 3879 0.0 1.3 468216 13972 ? Sl 12:06 0:00 kdeinit4: ksmserver [kdeinit] nbiser 3954 0.2 5.3 615296 54888 ? Sl 12:06 0:42 kwin nbiser 4601 0.0 7.9 1190884 81192 ? Sl 12:06 0:14 kdeinit4: plasma-desktop [kdeinit] nbiser 4621 0.0 2.8 1017080 29136 ? Sl 12:06 0:01 /usr/bin/knotify4 nbiser 5194 0.0 1.6 249576 16480 ? S 12:06 0:00 /usr/bin/kuiserver nbiser 5473 0.0 1.2 400692 12940 ? S 12:06 0:00 kdeinit4: kaccess [kdeinit] nbiser 5480 0.0 0.5 388660 5844 ? Sl 12:06 0:00 kdeinit4: nepomukserver [kdeinit] nbiser 5483 0.1 1.8 224480 18996 ? S 12:06 0:32 /usr/bin/vmtoolsd -n vmusr --blockFd 3 nbiser 5486 0.0 3.0 868848 31632 ? SNl 12:06 0:00 /usr/bin/nepomukservicestub nepomukstorage nbiser 5488 0.0 2.9 761384 29932 ? Sl 12:06 0:03 kdeinit4: krunner [kdeinit] nbiser 5496 0.0 1.6 344824 16792 ? Sl 12:06 0:00 /usr/lib64/kde4/libexec/polkit-kde-authentication-agent-1 nbiser 5497 0.0 1.4 252564 15092 ? S 12:06 0:00 /usr/bin/nepomukcontroller nbiser 5500 0.0 1.3 407260 13472 ? S 12:06 0:00 kdeinit4: klipper [kdeinit] nbiser 5502 0.0 1.9 546116 20068 ? Sl 12:06 0:00 kdeinit4: kmix [kdeinit] nbiser 5508 0.0 0.6 361828 6416 ? Sl 12:06 0:01 /usr/bin/pulseaudio --start nbiser 5545 0.0 0.5 121668 5296 ? Sl 12:06 0:00 /usr/bin/akonadi_control nbiser 5548 0.0 1.2 718828 12644 ? Sl 12:06 0:00 akonadiserver nbiser 5550 0.0 3.2 789160 33064 ? Sl 12:06 0:06 /usr/sbin/mysqld --defaults-file=/home/nbiser/.local/share/akonadi/mysql.conf --datadir=/home/nbiser/.local/share/akonadi/db_d nbiser 5590 0.0 1.7 276940 17916 ? Sl 12:06 0:00 /usr/bin/akonadi_agent_launcher akonadi_akonotes_resource akonadi_akonotes_resource_0 nbiser 5591 0.0 1.7 270476 17916 ? Sl 12:06 0:00 /usr/bin/akonadi_agent_launcher akonadi_contacts_resource akonadi_contacts_resource_0 nbiser 5592 0.0 1.9 273112 20168 ? Sl 12:06 0:00 /usr/bin/akonadi_agent_launcher akonadi_ical_resource akonadi_ical_resource_0 nbiser 5593 0.0 1.8 276912 18396 ? Sl 12:06 0:00 /usr/bin/akonadi_agent_launcher akonadi_maildir_resource akonadi_maildir_resource_0 nbiser 5594 0.0 2.1 309064 21776 ? S 12:06 0:00 /usr/bin/akonadi_maildispatcher_agent --identifier akonadi_maildispatcher_agent
Code:
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
633 root 20 0 229m 60m 18m S 1.0 6.0 2:13.00 Xorg
17045 nbiser 20 0 504m 32m 17m S 0.7 3.3 0:10.66 konsole
590 root 20 0 148m 3464 3128 S 0.3 0.3 0:24.19 vmtoolsd
3954 nbiser 20 0 616m 53m 33m S 0.3 5.4 0:46.95 kwin
5483 nbiser 20 0 219m 18m 14m S 0.3 1.9 0:33.32 vmtoolsd
1 root 20 0 43608 2976 1988 S 0.0 0.3 0:02.49 systemd
2 root 20 0 0 0 0 S 0.0 0.0 0:00.01 kthreadd
3 root 20 0 0 0 0 S 0.0 0.0 0:00.40 ksoftirqd/0
6 root rt 0 0 0 0 S 0.0 0.0 0:00.00 migration/0
7 root -2 0 0 0 0 S 0.0 0.0 0:18.07 rcuc/0
8 root rt 0 0 0 0 S 0.0 0.0 0:00.00 rcun/0
9 root -2 0 0 0 0 S 0.0 0.0 0:00.00 rcub/0
10 root rt 0 0 0 0 S 0.0 0.0 0:00.00 rcun/1
11 root -2 0 0 0 0 S 0.0 0.0 0:00.00 rcub/1
12 root rt 0 0 0 0 S 0.0 0.0 0:02.10 watchdog/0
13 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 cpuset
14 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 khelper
15 root 20 0 0 0 0 S 0.0 0.0 0:00.00 kdevtmpfs
16 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 netns
17 root 20 0 0 0 0 S 0.0 0.0 0:00.10 sync_supers
18 root 20 0 0 0 0 S 0.0 0.0 0:00.00 bdi-default
19 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kintegrityd
20 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kblockd
21 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 ata_sff
22 root 20 0 0 0 0 S 0.0 0.0 0:00.00 khubd
23 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 md
24 root 20 0 0 0 0 S 0.0 0.0 0:00.00 khungtaskd
25 root 20 0 0 0 0 S 0.0 0.0 0:01.37 kswapd0
26 root 25 5 0 0 0 S 0.0 0.0 0:00.00 ksmd
27 root 39 19 0 0 0 S 0.0 0.0 0:01.79 khugepaged
28 root 20 0 0 0 0 S 0.0 0.0 0:00.00 fsnotify_mark
29 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 crypto
33 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kthrotld
35 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kpsmoused
37 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 deferwq
72 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kmpath_rdacd
126 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 mpt_poll_0
127 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 mpt/0
129 root 20 0 0 0 0 S 0.0 0.0 0:00.00 scsi_eh_0
131 root 20 0 0 0 0 S 0.0 0.0 0:01.53 kworker/u:2
194 root 20 0 0 0 0 S 0.0 0.0 0:00.85 jbd2/sda2-8
Top is probably better than ps because it shows the processes that are being run in real time, thus giving a better idea of the processes that are using up the most RAM and CPU time.
We can now move on to ending processes.
If you need to end a process use ps or top to determine the PID, you then type this command:
Code:
kill -s sigkill pid
We now come to redirecting text. Lets say that use use the command ps -e, but the output is too long to display on the screen. To get around this problem you need to type:
Code:
ps -e >example.txt
To create a directory you need to type
Code:
mkdir directoryname
Finally, we come to removing files and directories. Lets say that you have a file named ezyremove.txt, and you wish to remove it. To do so you should tyep:
Code:
rm ezyremove.txt
To erase a directory your need to type
Code:
rmdir exampledirectory
Total Comments 1
Comments
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Thanks again.!!!Posted 06-20-2013 at 09:23 AM by vmccord 
