Copying File Command

It copies a file or a group of files. Copying file overwrites without warning the destination file if it already exists.

SYNTAX: $cp  <source>  <target>

Example:

$cp   file1  file

$cp  file1  file2  dir1 (used for copying file to directory)

Remove Directory Command

Used to delete a directory.

SYNTAX: $rmdir  <dir>

Example:

$rndir  unix

Change Directory Command

It is used to change from one directory to other.

SYNTAX: $cd   <dir>
       
Example:

$cd  unix1

Note: cd.. or cd\ is used to come out from directory

Making Directory Command

It is used to create directory

SYNTAX: $mkdir   <dirname>
                 $mkdir  <dir>  <dir>/<subdir>   <dir1>/<subdir1>

Example:

$mkdir  Unix
$mkdir  Unix  Unix/u  (Used to create sub directories)
$mkdir  test
output: mkdir : can't make test directory

Uname Command

It is used to display operating system and the version user is using.

SYNTAX: $uname

Example:

$uname  -r  (Used to display version)
$uname  -s (Used to display what is operating system & what we are using)
$uname  -n (Used to display the host or server name)

Echo Command

This command is used to display the message on the screen.

SYNTAX: $echo "message"

Example:

$echo "Welcome to Unix"

Who Command

This command will provide all current users of the system working on various terminals.

SYNTAX: $who

Example:

$who i am
$who -HU (used to display all details of user)

Basic Calculator Command

It is used to perform arithmetic operations.

SYNTAX: $bc

Examples:
$bc
1+2
3
$1*2
2
$bc
12/2
6
$bc
0 base =2
14
1110

Date Command

It is used to display  the current date.

SYNTAX:  $date

Examples:
$date
$date  +%m (this is used display no.of months)
$date +%h   (this is used to display name of the month)
$date '%h%m'
$date +%y  (used to display last 2 digits of year)
$date +%D  (used to display mm/dd/yy)

Calender command

It's a handy tool that you can invoke any time to see the calender of any specific month or a complete year.

SYNTAX: $cal

Example:
$cal
$cal  03 2012
$cal 2012 | more (' |' pipe symbol is used to combine two commands. The o/p of one command may give to i/p of next command)