UNIX COMMANDS

UNIX Commands

1.    To create a directory.

a.    Syntax : mkdir (directory name)

b.    Example : mkdir CIVIL

2.    To rename a directory.

a.    Syntax : mv (directory 1) (directory 2)

b.    Example : mv CIVIL IT

3.    To change the directory.

a.    Syntax : cd (directory name)

b.    Example : cd IT1

4.    To copy the directory and its file to another directory.

a.    Syntax : cp –r (source directory) (destination directory)

b.    Example : cp –r IT1/ IT2

5.    To remove directory.

a.    Syntax : rmdir (empty directory name)

b.    Example : rmdir IT1

c.     Syntax : rmdir –r (non-empty directory name)

d.    Example : rmdir –r IT2

6.    To print present working directory. / To display complete path of the working directory.

a.    Syntax : pwd

7.    To create a file.

a.    Syntax : vi (file name)

b.    Example : vi aa.txt

8.      To rename a file.

a.    Syntax : mv (old file name) (new file name)

b.    Example : mv aa.txt a1.txt

9.      To view / display a file.

a.    Syntax : cat (file name)

b.    Example : cat a1.txt

10.    To copy files.

a.    Syntax : cp (source filename) (destination filename)

b.    Example : cp a1.txt a2.txt

11.    To move files.

a.    Syntax : mv (filename 1) (filename 2)

b.    Example : mv a1.txt a2.txt

12.    To list the contents of a directory.

a.    Syntax : ls

13.    To view first 10 lines of a file / to display the beginning of a file

a.    Syntax : head (file)

b.    Example : head a1.txt

14.    To view last 10 lines of a file / to display the end of a  file

a.    Syntax : tail (file)

b.    Example : tail a1.txt

15.    To display a string.

a.    Syntax : echo (string)

b.    Example : echo “IRTT”

16.    To count the number of words, lines and characters in a file.

a.    Syntax : wc (file)

b.    Example : wc aa.txt

c.     Syntax : wc –w (file)         // Count number of words only

d.    Example : wc –w aa.txt

e.     Syntax : wc –l (file)           // Count number of lines in file

f.     Example : wc –l aa.txt

g.     Syntax : wc –m (file)         // Count number of characters in file

h.    Example : wc –m aa.txt

17.    To search for a specific word in a file.

a.    Syntax : grep (word) (file)

b.    Example : grep civil aa.txt

18.    To count the number of occurrence of a character in a file.

a.    Syntax : grep –c (word) (file)

b.    Example : grep –c civil aa.txt

19.    To view the commands which was executed

a.    Syntax : history

20.    Show manual for a command

a.    Syntax : man (command)

b.    Example : man cat

21.    To clear the screen.

a.    Syntax : clear

22.    To print the calendar

a.    Syntax : cal

b.    Syntax : cal (year)

c.     Example : cal 2013

d.    Syntax : cal (month) (year)

e.     Example : cal 3 2012

23.    To print date and time.

a.    Syntax : date

24.    To find out who is logged in. / To print who is using the system presently.

a.    Syntax : who

25.    Display user name.

a.    Syntax : whoami

26.    Display users full detail, user-id and group-id.

a.    Syntax : id