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7/31/2019 Stud Towrite

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Ex no:2 BASIC UNIX COMMANDS

AIM:

To execute UNIX general purpose commands in UNIX Operating system

1. THE DATE COMMAND

The date command is used to display the current date with day of week, month, Day,time (24 Hours clock) and the year.

Syntax: $date

Example: $date

Output: Mon Sep 3 23:33:45: 1 st 2005

( It display the current day, month, date, year, hours, minutes, seconds)

OPTION : $ date +%m ( 02months digits)

$ date +%h ( Febmonths letters)

$ date +%d ( 08date digits)

$ date +%y ( 11year last two digits)

$ date +%H ( 22Hours)

$ date +%M ( 02minutes)

$ date +%S ( 02Seconds)

2. THE ECHO COMMAND

The echo command is used to print the message on the screen

Syntax: $echo text

Example: $echo learning UNIX

Output: learning UNIX

3.THE UNIX CALENDER: CAL


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The calendar (cal) command helps us to keep track of our days .It displays the specifiedmonth or year calendar.

Syntax: $cal month or year

Example 1: $cal 2011

Output: prints the calendar for the entire year

Example 2: $cal 9 2011

Output: prints the calendar for the month of September 2011

4. UNIX CALCULATOR:BC

UNIX offers an online calculator and can be invoked by the command bc. Thiscalculator is programmable and has complex functions.

Syntax: $bc

Example: $bc

Output: 5+5

10

( bc continuous this process until your given CTRL + D to terminate)

5. THE WHO COMMAND

The who command is more powerful and used to displays data about all the users, whoare currently logged into the system.

Syntax: $who

Example1: $who

Output: user1 tty1 Sep 03 09:30

(It display the output login name, terminal line, login date and time)

Example 2: $whoh

Output: NAME LINE TIME

user1 tty1 Sep 03 09:30

(display the column header)


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6. THE WHO AM I COMMAND

The whocommand with am and idisplay a single line of output pertaining to thelogin details of the user.

Example: $ who am i

Output: User1 tty1 Apr 4 09:30

(It identifiers the user and lists the user name, terminal line, the date and time of login)

7. THE FINGER COMMAND

The finger command gathers and displays the information about the users, whichincludes login name, real name, home directory etc.

Syntax: $finger username

Output: login name: root name: root

Directory: / root shell:/bin/bash

On since wed Jan 19 23:20 (IST) on pst/0 from 192.168.1.29

2 hours 2 minutes idle

On since Thu Jan 20 23:20 (IST) on pst/1 from 192.168.1.14

New mail received wed Jan 19 21:20 2011 (IST)

Unread since Thu Dec 20 23:20 2010 (IST)

No plan

(To display such information of a particular user)

Example 2: $finger

Login name Tty idle login time office office phone

root root pts/0 2:01 Jan 18 20:10 (192.168.1.29)

(Display the information about all users who are currently logged on)


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8 THE ID COMMAND

The id command is used to display the numerical value that corresponds to your loginname .UNIX user is assigned a login name, a user- id and a grouped- id

Syntax: $ id

Example: $ id

Output: uid= 347(user1) gid= 50(group)

9. THE TTY COMMAND

The tty (teletype) command is used to know the terminal name that we are using.

Syntax: $ tty

Eg : $ tty

Output: /dev/tty1

(Means, the terminal file tty1 resident in /dev directory.)

10 .CHANGE THE PASSWORD: PASSWD

If your account still does not have a password , or has one that is already known toothers, the password can be changed by using the passwd command.

Syntax: $ passwd

Output: UX: passwd: INFO: changing password for local

Old password : ***********

New password: ***********

Re-Enter New password: *****

Result:

Thus the above commands has been verified and executed.


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Ex no:3 WORKING WITH FILES

AIM:

To create a file and working with file using UNIX.

DEFINITION:

A file in a collection of related information such as letters, numbers, some specialcharacters and it may be a program.

FILE SYSTEM:

A file system is a group of files containing relevant information regarding it. Everythingin UNIX can be represented by a file such as directories, device drivers etc..

FILE IN UNIX:

File has divided into four categories

Ordinary files Directory files Special files Standard files

FILE COMMAND:

UNIX provides the file command to determine the types of file.

Syntax: $ file filename

Example: $ file shivani

Output: shivani ascii text

1. CREATE A FILEThe cat command is used to create a new file

Syntax: $ cat > filename

Example: $cat > test

My first file is UNIX

UNIX is a multi-user OS

(After finished typing, press CTRL+D)


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2. DISPLAY A FILE:

The cat command is also used to viewthe content of a file

Syntax: $ cat filename

Example: $ cat test

Output: My first file is UNIX,UNIX is a multi-user OS

3 MERGE THE FILE:

Cat commandservices to concatenated multiple files into asingle file

Syntax: $ cat file file1 >file2

Example: $ cat test test1>test2

Output: cat test

My first file is UNIX, UNIX is a multi-user OS

Cat test1

Os is software

Cat test test1 >test2

Cat test2


Os is software

4 COPING A FILE:

The cp command is used to copy the contents of one file to another.

Syntax:$ cp oldfile newfile

Example: $ cp test2 test3

Output: cat test2


Os is software.

Cp test2 test3


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Cat test3


Os is software

5 REMOVING A FILE:

The remove command is used to remove (or) erase an existing file.

Syntax: $ rm filename

Example: $ rm test3

Output: cat test3

No such a file

6 MOVING A FILE:

The mv command is used to move a file from one place to another

Syntax : $ mvoldfile newfile

Example: $ mv test2 test4

Output: cat test4


Os is software.

7 COUNTING NUMBER OF WORDS:

The wc command is used to count the number of words, lines, characters in a file

Syntax: $ wc filename

Example : $ wc filename

nl nw nc filename

where:

nlis the numbers of lines

nw - is the numbers of words


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nc - is the numbers of characters

output: $ wc test1

1 3 12 test1

Syntax: $ wc l file name (only line)

Syntax: $ wc w filename (only words)

Syntax: $ wc c filename (only characters)

8 SORTING THE CONTENT OF THE FILES:

The sort command is used for sort the contents of a file name.

Syntax : $ sort filename

Example: $ cat> mech

New

Morning

Apple

Output : $ sort mech

Apple

Morning

new

option: $ sort -r filename ( reverse order)

. $ sortc filename (disorder)

Result:

Thus the above command are verified and executed.


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Ex No:4 WORKING WITH DIRECTORIES

AIM

To learn about the working with directories using UNIX

1 CURRENT WORKING DIRECTORY

The pwd command is provided to know the current using directory.

Syntax : $ pwd

Example : $ pwd

Output : home 10me01

2 CREATE A DIRECTORY

A mk dir is used to create an empty directory in a desk.

Syntax : $ mk dir directory name

Example : $ mk dir MECH

3 REMOVING A DIRECTORY:

The rmdir is used to remove a directory from the disk before removing the directory mustbe empty.

Syntax : $ rmdir directory name

Option: rmdir -r file name ( search delete the file and subdirectories)

rmdir -I filename (warn message)

rmdie -f filename (write protected)

4 CHANGING THE WORKING DIRECTORY:

The cd command is used to changing the directory from one directory to another.

Syntax : $ cd directory name


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5 THE PATH :

The path command is used to specify the current path of the operating system

Syntax : $ echo $ PATH

(root of path will be display)

6 CLEARING THE SCREEN :

Clear command is used to clear the screen

Syntax : $ tput clear

RESULT :

Thus the above commands has been executed and verified successfully.


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ExNo:6 PIPES

AIM:

To learn about the pipes in UNIX a pipe is a mechanism by which output ofthe one command can be used into the input of another command is effected by thecharacter ( | ) And which is paced between the two characters.

Syntax: $ who | wc -l

Syntax: $ ls | sort | wc -l

THE TEE COMMAND

The tee command copies the incoming data on input to output,in the mean time it saves acopy in specified file.

Syntax: $ command | tee file

Example: $ who | tee sample | wc -l

RESULT:

The above commands has been executed and verified successfully.


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ExNo:7 WORKING WITH FILTERS

AIM:

To study a about simple filter using UNIX

1. THE HEAD FILTERAs the name simples the displays the first ten lines of a file.Syntax: $ head file name

example: $ head -13 myfile

2. THE TAIL FILTER:-The tail command is the opposite to the head command. It displays 10 lines of a file

from the end of the file.

Syntax: $ tail file name

Example: $ tail myfile

3. THE MORE COMMANDTo continue scrolling with the more command, you have

to press space barnot the Enter keyas in pg command.

Syntax: $ more myfile

Syntax: $ More file 2 file 3.

4. THE GREP Command:-It is used to search and print specified pattern form file.

Syntax: Grep [option] pattern file(s)

Example: $ grep Asia data

5. THE UNDO COMMAND

We just saw not soft remove then the n option.


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6 ADDING LINE NUMBERS NL

The nl filter adds line numbers to a file and it displays the file and not provides accessto edit but simply displays the contents on the screen. The following filter adds line number

To a specified file.

Syntax: $ nl file name

7.SELECTING FIELDS FROM A LINE-CUT:

We can select specified files from a line

of text using cut command.

Syntax: $ cutc file name

Where

-c : option cut on the specified character

position from each line.

filename :specifies name of the file.

8 PASTING FILES:

When you cut some of the characters in a file using the cut command those can be pastedback with the paste command.

Syntax: $ paste command

Example: $ paste std

9. COMPARTING FILES

To know weather two files are identical in all respects so that one of item may be deleted.This cmp command is used to carryout this task.

Syntax: $ cmp file1 file 2

Example: $ cmp std1 std2


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10. COMPARISON & DIFFERENCES

Comm command is used to compare two sorted files, and compares each line of the first filewith its corresponding line in the second.

The diff command can be used to display file differences but unlike it follow members cmp

and comm. It also tells you which lines in one file have to be changed to make the two filesidentical.

Syntax: $ comm. File1 file2

Syntax: $ diff file1 file 2

Result:

Thus the above commands have been executed successfully.


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Ex. No:8


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Ex. No:9

Ex. No:10


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COMMAND LINE ARGUMENT

Ex no : ADDING THE COMMAND LINE ARGUMENTS

AIM:

To write a shell program for using command line arguments.

ALGORITHM:

Step 1: Start the program

Step2: Read the arguments

Step3: Initialize the total

Step4: Loop to calculate the sum of arguments

Step5: Print the sum of arguments

Step6: Stop the program

RESULT:

Thus the program has been executed .


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Ex no 9b: SHIFTING THE COMMAND LINE ARGUMENTS

AIM:

To write a shell program for using command line arguments .

ALGORITHM:



Step3: Initialize the arguments

Step4: shift the arguments

Step5: Print the result

Step6: Set the value for arguments


RESULT:



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Ex no 9c: PRINTING THE NUMBER OF ARGUMENTS

AIM:

To write a shell program for using command line arguments .

ALGORITHM:



Step3: Conditional statement to they determine the number of arguments

Step4: Print the number of arguments


RESULT:



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11. DYNAMIC STORAGE ALLOCATION

Ex no 11a: DYNAMIC STORAGE OF AN ARGUMENT

AIM:

To write a C program for dynamic storage of an argument.

ALGORITHM:


Step2: Read the argument value.

Step3: To locate the memory address of the argument value.

Step4: Print the address of the argument.


RESULT:

Thus the program has been executed.


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Ex no 11b: DYNAMIC MEMORY ALLOCATION USING MALLOC()

AIM:

To write a C program for dynamic memory allocation using malloc().

ALGORITHM:


Step2: Read the number of students using malloc().

Step3: Read the marks of students.

Step3: To calculate the average of the marks of the students.

Step4: Print the average of the marks.Step6: Stop the program

RESULT:



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12.FUNCTIONS

Ex no 12A:FINDING ncr USING FACTORIAL FUNCTIONAIM:

To write a C program for finding ncr using factorial function

ALGORITHM:


Step2: Read the value of n and r.

Step3: Write a function for factorial fact().

Step4: using factorial function fact() calculate the ncr value.

Step5: Print the result value of ncr.


RESULT:



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Ex no 12b:COSINE SERIES USING FUNCTIONAIM:

To write a C program for finding cosine series using function.

ALGORITHM:


Step2: Let the x value of cosine series starts with 0.

Step3: Write a function for cosine calculation cosine().

Step4: using cosine function cosine() calculate cosine series from 0 to 180 degree.

Step5: Print the cosine series value from 0 to 180 degree.


RESULT:



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Ex no 12c:FUNCTION WITH ARGUMENTS AND RETURN VALUES

AIM:To write a C program for finding largest among 2 numbers using function.

ALGORITHM:


Step2: Read the function arguments.

Step3: Write a function largest(int a1,int b1).

Step4: Find the largest number calling largest().

Step5: Return the largest value to the main() function.

Step5: Print the largest value.


RESULT:



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13.POINTERS

Ex no 13a: Basic Calculator using pointers

AIM:To write a C program to perform Arithmetic operations using pointers.

ALGORITHM:


Step2: Read the values for the pointer variables.

Step3: Using switch statement select any one of the operation addition, subtraction,

multiplication, division or modulus.

Step4: Find the result of the operation.

Step5: Print the result of the operation.

Step6: Stop the program.

RESULT:



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Ex no 13b: Pass by value and reference using pointers

AIM:

To write a C program to swap the value or reference using pointers.

ALGORITHM:


Step2: Read the values for the pointer variables.

Step3: Using the functions swapval() and swapref() swap the value and reference address

respectively.

Step4: Print the swapped output for swapval() and swapref().


RESULT:



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Ex no 13c: String copy using pointers

AIM:To write a C program to copy from one string to another using pointers.

ALGORITHM:


Step2: Read the string for the pointer variables.

Step3: create a function stringcopy().

Step4: Call stringcopy() to copy from source to destination.

Step5: Print the source string and destination string.


RESULT:



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14. FILE HANDLING

Ex no 14a: Displaying file contents

AIM:To write a C program to display the contents of file, imitating cat command using FILEpointer.

ALGORITHM:

Step1: Start the program

Step2: Read the file name at the command line.

Step4: Open the file and read the content.

Step5: Display the content of the file.


RESULT:



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Ex no 14b: Copying a file

AIM:To write a C program to copy file, imitating cp command using FILE pointer.

ALGORITHM:

Step1: Start the program.

Step2: Read the source and destination file names at the command line.

Step4: Open the file and read the content.

Step5: Copy the content to the destination file.

Step6: Display the content of the file.


RESULT:



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Ex no 14c: Write to a file character-by-character

AIM:To write a C program to input File using getc and putc functions using FILE pointer.

ALGORITHM:

Step1: Start the program.

Step2: File name is provided at the program.

Step4: On execution, type the contents of the file and press cntrl+D.

Step5: File contents are updated.

Step6: Using the cat command, display the content of the file.


RESULT:


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