Linux Basics !

What is difference between shell & kernal ?

The main difference between kernel and shell is that thekernel is the core of the operating system that controls all the tasks of the system while the shell is the interface that allows the users to communicate with the kernel. Unix is an operating system. It is the interface betweenthe user and the hardware.

Reference

https://pediaa.com/difference-between-kernel-and-shell/

Some shells:

bash

c

korn

How to open file ?

open 'filename' or cat 'filename'

Cosmis-MacBook-Air:Desktop cosmi$ cat vidushi.txt

How to create empty file ?

touch 'filename'

How to check date ?

date

How to check date ?

touch 'filename'

How to check in which directory you are ?

touch 'filename'

How to check in which directory you are  ?
 touch 'filename'

How to check in which directory you are ?

touch 'filename'

Possible ways to use 'less command' ?

How to remove folder with directories & folders inside ?

rm -rf ws

Reverse contents of file

cosmi$ rev

Takshila

alihskaT

mv

wsip-174-79-41-8:test cosmi$ ls

test1 v11 copy.txt v13.txt v2 copy.txt v4 copy.txt v6.txt v9 copy.txt

test2 v11.txt v14 copy.txt v2.txt v4.txt v7 copy.txt v9.txt

v1 copy.txt v12 copy.txt v14.txt v21.txt v5 copy.txt v7.txt

v10 copy.txt v12.txt v15 copy.txt v3 copy.txt v5.txt v8 copy.txt

v10.txt v13 copy.txt v15.txt v3.txt v6 copy.txt v8.txt

wsip-174-79-41-8:test cosmi$ mv v2.txt /Users/cosmi/test/test1/

less

less

ps -ef | less

Reference

https://www.lifewire.com/what-to-know-less-command-4051972

https://www.thegeekstuff.com/2010/02/unix-less-command-10-tips-for-effective-navigation/

https://www.lifewire.com/what-to-know-less-command-4051972

wc

wc stands for word count. As the name implies, it is mainly used for counting purpose.

It is used to find out number of lines, word count, byte and characters count in the files specified in the file arguments.
By default it displays four-columnar output.
First column shows number of lines present in a file specified, second column shows number of words present in the file, third column shows number of characters present in file and fourth column itself is the file name which are given as argument.

wsip-174-79-41-8:~ cosmi$ cd test

wsip-174-79-41-8:test cosmi$ wc v1.txt

39 560 3501 v1.txt

wsip-174-79-41-8:test cosmi$ wc v1.txt v2.txt

39 560 3501 v1.txt

0 0 0 v2.txt

39 560 3501 total

wsip-174-79-41-8:test cosmi$

Memory related commands

du

$du -a test
/*now using du to produce
sorted output */
$du -a test | sort -n

~ cosmi$ du |less -N

df

How to check in diskspace ?

df- diskspace .

Reference

https://www.geeksforgeeks.org/df-command-linux-examples/

File compression & extraction command

zip

wsip-174-79-41-8:~ cosmi$ zip test.zip test

adding: test/ (stored 0%)

unzip

tar

How to search in files ?

How to check in environment ?

Linux : printenv

$du -a test
/*now using du to produce
sorted output */
$du -a test | sort -n

Commands to shutdown or force reboot

reboot -f

reboot

shutdown

shutdown -h now

shutdown

* * * * * command to execute │ │ │ │ │ │ │ │ │ └─── day of week (0 - 6) (0 to 6 are Sunday to Saturday, or use names; 7 is Sunday, the same as 0) │ │ │ └──────── month (1 - 12) │ │ └───────────── day of month (1 - 31) │ └────────────────── hour (0 - 23) └─────────────────────── min (0 - 59)

Cosmis-MacBook-Air:Desktop cosmi$ crontab

1 * * * * * * date

* * * * * * echo "Takshila"

min hour date month dow

Cosmis-MacBook-Air:Desktop cosmi$ test $(time)

real 0m0.000s

user 0m0.000s

sys 0m0.000s

Cosmis-MacBook-Air:Desktop cosmi$ test $(date)

-bash: test: too many arguments

Cosmis-MacBook-Air:Desktop cosmi$

TEXTEDITOR
NANO
VI

CRON TAB
OPENS UP EDITOR

Cosmis-MacBook-Air:Desktop cosmi$ crontab -e

Getting permission to edit other s

Cosmis-MacBook-Air:Desktop cosmi$ su crontab -u cosmi

Password:

su: Sorry

Cosmis-MacBook-Air:Desktop cosmi$ 

Last login: Sun Apr  1 21:49:31 on ttys000

Cosmis-MacBook-Air:~ cosmi$ cd Desktop

java-version

chmod- Changing file mode

-bash: wakeup.sh: command not found

Cosmis-MacBook-Air:Desktop cosmi$ chmod +x wakeup.sh

Cosmis-MacBook-Air:Desktop cosmi$ bash wakeup.sh

mac os x

Cosmis-MacBook-Air:Desktop cosmi$ 

export- Setting environmental variables

export JAVA_HOME =/Library/Java/Home

export M2 =$M2_HOME/bin

export MAVEN_OPTS = -Xmx256m-Xmx512

export PATH = $M2:$PATH

Cosmis-MacBook-Air:Desktop cosmi$ ls

Atom alias

BOOKS -2018

CLOSURE

Postman alias

clear

pwd- show the files

Cosmis-MacBook-Air:Desktop cosmi$ pwd

/Users/cosmi/Desktop

Cosmis-MacBook-Air:Desktop cosmi$

list- show the list of files

Cosmis-MacBook-Air:Desktop cosmi$ ls -lrt

total 21208

-rw-r--r--@ 1 cosmi staff 948 May 3 2017 Eclipse

-rw-r--r--@ 1 cosmi staff 800 May 6 2017 pgAdmin 4

-rw-r--r--@ 1 cosmi staff 788 Jun 9 2017 STS

-rw-r--r--@ 1 cosmi staff 944 Jul 15 2017 Postman alias

-rw-r--r--@ 1 cosmi staff 928 Aug 5 2017 Atom alias

drwxr-xr-x@ 3 cosmi staff 102 Aug 10 2017 Skype.app

drwxr-xr-x@ 13 cosmi staff 442 Oct 25 11:31 Umlet

-rw-r--r--@ 1 cosmi staff 171 Oct 30 12:36 ~$FINANCE.xlsx

drwxr-xr-x@ 46 cosmi staff 1564 Dec 15 19:00 CODING EXAMPLES

-rw-r--r--@ 1 cosmi staff 210141 Jan 11 15:30 CV.pdf

drwxr-xr-x 6 cosmi staff 204 Jan 24 11:34 spring-main

drwxr-xr-x 40 cosmi staff 1360 Feb 26 16:07 CLOSURE

drwxr-xr-x 10 cosmi staff 340 Mar 1 16:14 H1-B

touch [-A [-][[hh]mm]SS] [-acfhm] [-r file] [-t [[CC]YY]MMDDhhmm[.SS]] file ...

Cosmis-MacBook-Air:Desktop cosmi$ touch -r wakeup.sh

usage:

touch [-A [-][[hh]mm]SS] [-acfhm] [-r file] [-t [[CC]YY]MMDDhhmm[.SS]] file ...

touch- Create new file

Cosmis-MacBook-Air:Desktop cosmi$ touch vidushi.txt

Cosmis-MacBook-Air:Desktop cosmi$ touch -t YYMMDDHHMM.SS tecmint

Cosmis-MacBook-Air:Desktop cosmi$

cat-Read the contents of new file

Cosmis-MacBook-Air:Desktop cosmi$ cat vidushi.txt

HI Takshila !

I hope you get up see a brighter day !

you Deserve it baby

Regards

Vidushi

cp - To copy one or more files to another location.

Cosmis-MacBook-Air:Desktop cosmi$

head - to read first n lines} used with logs

Cosmis-MacBook-Air:~ cosmi$ cd Desktop

Cosmis-MacBook-Air:Desktop cosmi$ head vidushi.txt

Cosmis-MacBook-Air:Desktop cosmi$ head -15 vidushi.txt

Cosmis-MacBook-Air:Desktop cosmi$ head -5 vidushi.txt

Cosmis-MacBook-Air:Desktop cosmi$ head -n 4 *.txt

hihiiiiiiiiiiii

aaaaaaaaaaaa

tail - to read first n lines used with logs

bkbjkhjh

Cosmis-MacBook-Air:Desktop cosmi$ tail -100 vidushi.txt

su- changing user .

Cosmis-MacBook-Air:Desktop cosmi$ Iam@peace

-bash: Iam@peace: command not found

Cosmis-MacBook-Air:Desktop cosmi$ su postgres

Password:

su: Sorry

Cosmis-MacBook-Air:Desktop cosmi$

df- diskspace .

Cosmis-MacBook-Air:Desktop cosmi$ df

Filesystem 512-blocks Used Available Capacity iused ifree %iused Mounted on

/dev/disk1 487882752 172922432 314448320 36% 2176290 4292790989 0% /

devfs 358 358 0 100% 620 0 100% /dev

map -hosts 0 0 0 100% 0 0 100% /net

map auto_home 0 0 0 100% 0 0 100% /home

/Applications/sts-bundle/STS.app 487882752 173156032 314214720 36% 2176485 4292790794 0% /private/var/folders/p9/t2pt77xd77z4k4qlsq2pqy6c0000gn/T/AppTranslocation/12746F0F-436A-413B-9342-7CFB7B3A25D8

du- disk usage.

Cosmis-MacBook-Air:Desktop cosmi$ du

env- environment.

Cosmis-MacBook-Air:Desktop cosmi$ env

TERM_PROGRAM=Apple_Terminal

SHELL=/bin/bash

TERM=xterm-256color

TMPDIR=/var/folders/p9/t2pt77xd77z4k4qlsq2pqy6c0000gn/T/

Apple_PubSub_Socket_Render=/private/tmp/com.apple.launchd.85T4B3WwtO/Render

TERM_PROGRAM_VERSION=388.1.1

OLDPWD=/Users/cosmi

TERM_SESSION_ID=4B5D5D77-84D3-4ECB-92A3-B75D577DE595

USER=cosmi

SSH_AUTH_SOCK=/private/tmp/com.apple.launchd.AK4CN05Wkm/Listeners

__CF_USER_TEXT_ENCODING=0x1F5:0x0:0x0

PATH=/Library/Frameworks/Python.framework/Versions/3.6/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin

PWD=/Users/cosmi/Desktop

LANG=en_US.UTF-8

XPC_FLAGS=0x0

XPC_SERVICE_NAME=0

SHLVL=1

HOME=/Users/cosmi

LOGNAME=cosmi

_=/usr/bin/env

Cosmis-MacBook-Air:Desktop cosmi$ printenv

TERM_PROGRAM=Apple_Terminal

SHELL=/bin/bash

TERM=xterm-256color

TMPDIR=/var/folders/p9/t2pt77xd77z4k4qlsq2pqy6c0000gn/T/

Apple_PubSub_Socket_Render=/private/tmp/com.apple.launchd.85T4B3WwtO/Render

TERM_PROGRAM_VERSION=388.1.1

OLDPWD=/Users/cosmi

TERM_SESSION_ID=4B5D5D77-84D3-4ECB-92A3-B75D577DE595

USER=cosmi

SSH_AUTH_SOCK=/private/tmp/com.apple.launchd.AK4CN05Wkm/Listeners

__CF_USER_TEXT_ENCODING=0x1F5:0x0:0x0

PATH=/Library/Frameworks/Python.framework/Versions/3.6/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin

PWD=/Users/cosmi/Desktop

LANG=en_US.UTF-8

XPC_FLAGS=0x0

XPC_SERVICE_NAME=0

SHLVL=1

HOME=/Users/cosmi

LOGNAME=cosmi

_=/usr/bin/printenv

Cosmis-MacBook-Air:Desktop cosmi$

Cosmis-MacBook-Air:Desktop cosmi$ who

cosmi console Apr 1 21:25

cosmi ttys000 Apr 1 22:53

Cosmis-MacBook-Air:Desktop cosmi$ whoami

cosmi

Cosmis-MacBook-Air:Desktop cosmi$

Cosmis-MacBook-Air:Desktop cosmi$ find vidushi.txt

vidushi.txt

Cosmis-MacBook-Air:Desktop cosmi$ find vidushi.txt

find: vidushi.txt: No such file or directory

Cosmis-MacBook-Air:Desktop cosmi$ find vidushi.txt

vidushi.txt

Cosmis-MacBook-Air:Desktop cosmi$

less- filename | to read contents of file.

Cosmis-MacBook-Air:~ cosmi$ less vidushi.txt

vidushi.txt: No such file or directory

Cosmis-MacBook-Air:~ cosmi$ cd Desktop/

Cosmis-MacBook-Air:Desktop cosmi$ less vidushi.txt

kill process no

Cosmis-MacBook-Air:~ cosmi$ ps -ef|grep java

501 1403 1391 0 9:56AM ttys000 0:00.00 grep java

Cosmis-MacBook-Air:~ cosmi$ kill 1391

Cosmis-MacBook-Air:~ cosmi$

------------------------------------------------------------------------------------------------

GREP i

Cosmis-MacBook-Air:Desktop cosmi$ ps -ef|grep java

501 1641 1629 0 11:38AM ttys005 0:00.00 grep java

Cosmis-MacBook-Air:Desktop cosmi$ ps -ef|grep $(which java)

501 1644 1629 0 11:39AM ttys005 0:00.00 grep /usr/bin/java

Cosmis-MacBook-Air:Desktop cosmi$

grep does just text match, it doesn't have idea of process name or filename etc.

that is, if you have a python script called likejava.py, it will be in result too.

Back to your question, your *.java is not good, because grep works with regex, not glob patterns.

You could try:

ps -ef|grep $(which java) this will list java processes, but only for your default java installation. If you have more than one Java installed, e.g. your Jboss with java7, tomcat with java6, and eclipse with java5, this will fail.

There is another tool called pgrep. You could give it a try, e.g.

pgrep -l java

you could do man pgrep to get more info:

pgrep, pkill - look up or signal processes based on name and other attributes

EDIT add a small ps..|grep trick

just saw your output in the question:

You have grep *.java in output, it is a good example. grep *.java is not java process but it has text "java". so it is there.

You could avoid it by ps...|grep [j]ava works for bash.

Cosmis-MacBook-Air:Desktop cosmi$ ps -ef|grep java

501 1641 1629 0 11:38AM ttys005 0:00.00 grep java

Cosmis-MacBook-Air:Desktop cosmi$

------------------------------------------------------------------------------------------------

free : free memory

------------------------------------------------------------------------------------------------

ps | ps-t | ps-xsless : prints snap shot of current process

The ps (i.e., process status) command is used to provide information about the currently running

Cosmis-MacBook-Air:Desktop cosmi$ ps aux

USER PID %CPU %MEM VSZ RSS TT STAT STARTED TIME COMMAND

cosmi 1483 15.4 6.3 4046388 264948 ?? S 11:14AM 2:33.31 /Applications/Google Chrome.app/Contents/Versions/65.0.3325.181/Goog

cosmi 271 13.9 5.8 3999528 244628 ?? S 9:25PM 28:17.33 /Applications/Google Chrome.app/Contents/MacOS/Google Chrome -psn_0_

cosmi 453 3.4 1.1 3406548 47100 ?? S 9:25PM 0:23.94

Cosmis-MacBook-Air:Desktop cosmi$ ps -p 1483

PID TTY TIME CMD

1483 ?? 2:46.05 /Applications/Google Chrome.app/Contents/Versions/65.0.3325.181/Google Chrome Helper.app/Contents/MacOS/Google Chrome Help

Cosmis-MacBook-Air:Desktop cosmi$ ps -p 271

PID TTY TIME CMD

271 ?? 28:33.33 /Applications/Google Chrome.app/Contents/MacOS/Google Chrome -psn_0_28679

Cosmis-MacBook-Air:Desktop cosmi$

TOP - GIVES DETAILS OF

Processes: 265 total, 2 running, 263 sleeping, 1336 threads 11:31:29

Load Avg: 1.81, 1.88, 1.94 CPU usage: 12.44% user, 7.65% sys, 79.90% idle SharedLibs: 88M resident, 30M data, 7716K linkedit.

MemRegions: 52995 total, 805M resident, 38M private, 260M shared. PhysMem: 4072M used (1273M wired), 23M unused.

VM: 726G vsize, 633M framework vsize, 262014(0) swapins, 427719(0) swapouts. Networks: packets: 429346/530M in, 148614/20M out.

Disks: 402514/8529M read, 115953/4538M written.

PID COMMAND %CPU TIME #TH #WQ #PORT MEM PURG CMPRS PGRP PPID STATE BOOSTS %CPU_ME %CPU_OTHRS UID FAULTS COW

1567 top 3.6 00:00.62 1/1 0 20 2668K+ 0B 0B 1567 1541 running *0[1] 0.00000 0.00000 0 3843+ 105

1564 Google Chrom 0.0 00:00.36 15 1 134 12M 0B 11M 271 271 sleeping *0[1] 0.00000 0.00000 501 18605 1603

1559 mdworker 0.0 00:00.20 4 1 48 11M 0B 1132K 1559 1 sleeping *0[1]

top usage: top

[-a | -d | -e | -c ]

[-F | -f]

[-h]

[-i ]

[-l ]

[-ncols ]

[-o ] [-O ]

[-R | -r]

[-S]

[-s ]

[-n ]

[-stats ]

[-pid ]

[-user ]

[-U ]

[-u]

sudo ("superuser do", or "switch user do") allows a user with proper permissions to execute a command as another user, such as the superuser.
sudo allows a permitted user to execute a command as another user, according to specifications in the /etc/sudoers file.

ps | ps-t | ps-xsless : prints snap shot of current process

sudo

chmod -777

java -XX:+PrintFlagsFinal -version | grep -iE 'HeapSize|PermSize|ThreadStackSize'

pgrep -f desired_program_name

in progress

java -XX:+PrintFlagsFinal -version | grep -iE 'HeapSize|PermSize|ThreadStackSize'

pgrep -f desired_program_nameReferences

References

https://www.tecmint.com/11-cron-scheduling-task-examples-in-linux/

https://tecadmin.net/crontab-in-linux-with-20-examples-of-cron-schedule/

https://www.tecmint.com/11-cron-scheduling-task-examples-in-linux/

Java to linux communication

exit

whatis

clear

man

less

pwd

bash

cat

type

alias

whoami

whereis

date

touch

file

which

echo

nano

mkdir

head

tail

apropos

find

sort

uniq

cut

diff

comm

sdiff

paste

join

grep

sed

calender

cal

sleep

crontab

printenv/env

export

set

unset

stat

free

emacs

vim

history

kill

chsh

uname

jobs

dpkg

apt-get

apt-cache

aptitude

gzip

gunzip

bzip2

zip

tar

rsync

chmod R -777

chown

sudo

passwrd

adduser

ping

traceroute

ftp

wget

ssh

source

time

read

xargs

tee

printf

test

function

while

case

for

until

fold

top

vi filname

ps aux

java -XX:+PrintFlagsFinal -version | grep -iE 'HeapSize|PermSize|ThreadStackSize'

java -XX:+PrintFlagsFinal -version | grep -iE 'Xms|Xmx'

dzdo su

open /tmp

ls -la /tmp

rm /tmp

sudo rm /tmp

sudo rmdir /tmp

sudo unlink /tmp

unlink: /tmp: Operation not permitted

touch /tmp/test

ls -al /tmp

ls -al /tmp/

ls -la /var/log

ls -la /var/sfsite

cd /dist/

ls -l

rm sfsit

rmdir -f sfsite

rm -f sfsite

cd sfsite/

takshila:sfsite takshila.vidushi$ ls -la

takshila:sfsite takshila.vidushi$ cd ..

mv sfsite/ sfsiteold

ln -s ~/og

ln -s ~/og/

ln -s ~/og-deployment/dist/

ls -la

pwd

/dist

ln -s ~/og-deployment/dist/sfsite/

ls -la sfsite

lrwxr-xr-x 1 takshila.vidushi admin 50 Jun 5 16:21 sfsite -> /Users/takshila.vidushi/og-deployment/dist/sfsite/

ls -la sfsite/

ls -la /dist/

ls -la /dist/sfsite/

ls -latr /var/log/sfsite/

less /var/log/sfsite/groutingadmin.2019-06-05.log

less /var/log/sfsite/gateway.2019-06-05.log

2019-06-05 16:26:14,698 HttpTransportServlet INFO [ localhost-startStop-1]: Initialized CamelHttpTransportServlet[name=CamelServlet, contextPath=/gateway]

pgrep -f desired_program_name

-->

Cosmi

Monday, December 4, 2017

Linux Basics !

What is difference between shell & kernal ?

https://pediaa.com/difference-between-kernel-and-shell/

Some shells:

bash

c

korn

How to open file ?

open 'filename' or cat 'filename'

Cosmis-MacBook-Air:Desktop cosmi$ cat vidushi.txt

How to create empty file ?

touch 'filename'

How to check date ?

How to check date ?

touch 'filename'

How to check in which directory you are ?

touch 'filename'

How to check in which directory you are ?

How to check in which directory you are ?

Possible ways to use 'less command' ?

How to remove folder with directories & folders inside ?

rm -rf ws

mv

less

Reference

wc

du

df

How to check in diskspace ?

df- diskspace .

Reference

https://www.geeksforgeeks.org/df-command-linux-examples/

File compression & extraction command

How to search in files ?

How to check in environment ?

No comments:

Post a Comment

Monday, December 4, 2017

Linux Basics !

What is difference between shell & kernal ?

https://pediaa.com/difference-between-kernel-and-shell/ Some shells: bash c korn How to open file ? open 'filename' or cat 'filename' Cosmis-MacBook-Air:Desktop cosmi$ cat vidushi.txt

How to create empty file ?

touch 'filename'

How to check date ?

How to check date ?

touch 'filename'

How to check in which directory you are ?

touch 'filename'

How to check in which directory you are ?

How to check in which directory you are ?

Possible ways to use 'less command' ?

How to remove folder with directories & folders inside ? rm -rf ws

mv

less

du

df

How to check in diskspace ?

df- diskspace .

Reference

https://www.geeksforgeeks.org/df-command-linux-examples/

File compression & extraction command

How to search in files ?

How to check in environment ?

No comments:

Post a Comment

https://pediaa.com/difference-between-kernel-and-shell/

Some shells:

bash

c

korn

How to open file ?

open 'filename' or cat 'filename'

Cosmis-MacBook-Air:Desktop cosmi$ cat vidushi.txt

How to remove folder with directories & folders inside ?

rm -rf ws