unix command

pwd-present work directory

Ls-list of file. Cd change directory

Who-how many user is logged in

Whoami-directly who user is logged in

Man-manully online mannual information about commant

Who --count ---> No of user logged in

Who -b -->last time when system was logged in

cal-calender

cal -j-->julian calender

Cal -3 last 3 moth calender

Cal -m-->current month calender

cal -y---> current year command

Date +%a

Date +%A--.date in full form

Date +%b

Date +%B-->month in fulform

Date +%F-2016-08-23

Date +%y-year

How to create a file

Cat > NareshTech  ///promt allow to enter data enter data” hello word”

Note:$ user propmpt

       # admin prompt

See what ever is written in file

Cat NareshTech   or cat < NareshTech

Display data in numbered format

Cat -n NareshTech

Append in specific file

Cat >> NareshTech//will give prompt to append

Output of only non blank line:

Cat -b NareshTech

---

Touch ,mv,cp

Touch -->to create empty file

Touch file1 file2 file3 //3 file has been created

If u want to append something in file 1 use

Cat >> file1

Note to details of file-->  FILE *

Ls -l→ display file with details

touch  -m file1 //modificATION time

         -a file1 // access time

To modify access time use

touch -d ‘6 May 2016 20:32’ file1

Note stat file → give complete information about file

Mkdir dir1/dir2   //mkdir dir1 dir2

Note → current default location cd ~

           Current director cd -

rmdir→ remove directory empty directory // rm → to delete file in directory and Non empty directory

rm -i file2→ remove current file y/n   //i means iteractive

rm -v file2→ //message --removed file2   // v means verbose

rm -R dir1-->to delete complete directory

Mv linux unix→ rename linux to unix   // move cammand means mv

Mv -v unix /home/redhat/Hello/Linux-->inside hello i m moving unix and editing file with the name of  Linux -------here -v tell verbose means details of operation done

Mv -v /home/redhat/NareshTechnology/Unix   /home/redhat/NareshTechnology/Linux -->editing has been also done with complete directory information…..if u not pass new file name in updated directory move will be done by same name as previous file name

Cp→ copy //it by default work with file

Cp perl shell

Cp java javascript         ---------------// cp: ommiting directory ‘java’ here java and javascript are directory

Cp -r java javascript // r is recursive now copy of directory will done easily

U can also copy with details

Cp -v perl   /home/NareshTech/java -

--------//its same line mv command except here copy will done not move

---

Ls -l ---> long listing with details

Ls -t-->it display as based on time based// upaded first from start//time

Ls -rt->it display last updated first//time in reverse

Ls -s -->will  details file size wize

Ls ? -->display file having single charecter file name

Ls ??-->display having 2 character as file name

Ls ???--> 3 cahrecter

Rmdir ?--> simple character deleted

Rmdir ??-->double character file name deleted

Cat ? it display all file having single character file name

Cat ?? it display all file name having double character file name

Ls *a→ display all file ending with a

Rm *--> delete all file from current directory

Rm -r *--> it removes all file and subdirectory from current directory

Rmdir *-->it will remove all empty directory from current directory

Ls [abcd]* display all file or directory started with a or b or c or d  //Ls [a,b,c,d]*

Rm [a,b,c,d]* → remove director file started with a or b or c or d….it will work for rmdir alsowhich work on empty file

Ls [a-d]* display ALL File started with a or b or c or d

…………………………………………………………………..

-rw-rw-r--

“-”  →

“rw-”-->owner//who created file “u for owner”

“rw-”-->group/user  ...in which project collection are using “g for group”

“r--”-->for other  //”o for other”

Note:” a” for all

Chmod u+w,o-rwx -->adding write permission to owner and no permission to other

Ls-l  //long listing the file

-rw-rw----

assign execulatble permission

Chmod u=x Myfile //assingning executable permission

Chmod o=rwx Myfile//assining read write extecute prmission to other

Chmod a-rwx myfile //remove all permission fr0m all(owner ,group,other)

Note:

Rw- rw- r--

110 110 100   -------------------------->binary representation

6      6 4          --->simily for 0-7 digit

0 means no permission

Example:

Chomod 064 nacre  //no permission to owner ,rw permision to group and r permission to other

Ls -l

- --- rw- r-- 1 redhat 19 sep 21 13:52 nacre

---

1>Script:  //to save all which is written on terminal before “exit ” command

o/p:

Script started . file is typeScript //here filename which is defaut is typescript

Display script file ----> cat script//it will show all operation perform b/w script command and exit command

-->save all written operation on terminal session in between script and exit command

Script sraju//here sraju file will create

Note:script -a sraju→ Now script will on and append  all written text on terminal

2>bc //base convervion/// for calculator for mainlu c laguage it calculate till 11 permission ...here is one more command which is dc for unlimited pecision

3>

Uniq:print uniquness immediate after line

cat>cources

Unix

Unix

Linex

Linex

Unix

Js

Unix

Js

//uniq courses

Unix

Linex

Unix

Js

Unix

Js

Option:

Uniq -d courses

Unix

Linex

Uniq -c courses

2 Unix

2 Linex

1 Unix

1 Js

1 Unix

1 Js

-->uniq --count  couses

//display with count like -c option

4>logname:currently logged in username

5>users:current logged in user

6>which cat//tells cat command is available where

Which ls

//o/p:/bin/ls

Which  c++

/usr/bin/c++

7> whereis cat          //it tells various path where cat is available like “-m” for mannual path “-s” for static path

8>factor  //print prime factor of a number

Example:

Factor 4

2 2

9>echo To print like printf

Example

Echo helloworld

o/p:helloworld

$a=120;

$b=130;

$echo $a + $b

o/p: 120 + 130

$echo $[a+b];

o/p:250

$echo {a..d}

a b c d

$echo {a..z}//print a to z

$echo {A..Z}//print A to Z

$echo {A..z} //print A to Z and a to z

$echo {0..5}//print 0 to 5

$echo “hello, world !”//o/p error for this we have to write $echo “hello, world”! //bcz “!” has different meaning

$echo “welcome to echo in unix” >small

$cat small

o/p:welcome to echo in unix

$echo “welcome to echo in unix” >>small   // it will append text in small file

$echo “hello\nworld”

Output:hello\nworld

$echo -e “hello\nworld”

hello

World

$echo -e “Hello\n\tWorld”

Hello

     World

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

$cat >file1//it will give screen to write and  those line will finally store in file1 after ctrl +d

$cat <file1 // similar to “cat file1” it will shows content of file1  

$cat < file1 > file2 //its just like copy ..copying content of file1 to file2

---------

$wc -l file1//count no of line in file1  “l for line “//wc means word count ….this command  is similar to

$cat file1 | wc -l //0/p:2

$cat file |wc -l >line //this command will store o/p “2” in “line” file

$cat line

o/p:2

--....

$who --count //count no of user logged in

2

$who --count | wc -l >users1//$who --count will  be for o/p in numbered format

$cat users

2

$ls

Line unix user user1

$ls | wc -w

4

$ls | wc -w >file1 //here 5 will store in file 1 bcz fil1 is creating and remaining 4 file so 1+4=5

$cal file //o/p:5