Unix Command Practice Assignment – 2

Assignment – 2


1)Create a file containing some text Display the first line of the file containing
the string “Good Day”
Ans: [cmsa1@localhost ~]$ grep "good day" a11.txt

2)List all files in the present directory whose 2nd character
is a digit.
Ans: [cmsa1@localhost ~]$ ls ?[0-9]*

3)Compute prime factors of 28
Ans: [cmsa1@localhost ~]$ factor 28

4) Display all lines in a file which contain the word
‘Best’ from a file a11.txt.
Your command should report all occurrences of the word like Best,BeSt,BESt etc.
Ans: [cmsa1@localhost ~]$ grep -i "best" a11.txt

5)A file contains some records with record containing
 Name of city, Name of state,Name of country. Sort the file with ‘Name of stete’
as sort key.
Ans: [cmsa1@localhost ~]$ sort -t "|" -k 3 state.txt
     Here state.txt is the file and 3rd field is name of state.

6)Create a regular file. Write command to remove all 
permissions from the file.
Ans: [cmsa1@localhost ~]$ touch f1
     [cmsa1@localhost ~]$ chmod 000 f1
     Here f1 is the regular file whose all permissions are removed.

7)Combine the contents of the file t1 and t2 into
 another file t1t2.
Ans: [cmsa1@localhost ~]$ cat t1 t2 > s1s2

8)Convert all uppercase letters in a file
 f1 to lowercase letters.
Ans: [cmsa1@localhost ~]$ cat f1.txt | tr "[a-z]" "[A-Z]"

9)Merge and sort the contents of three text files (say a,b,c)
 and display the sorted ouput on the screen.
Ans: [cmsa1@localhost ~]$  cat a.txt b.txt c.txt | sort

10)List all lines in a file, which do not end
 with a semicolon.
Ans: [cmsa1@localhost ~]$ grep -v  ";"$ s123.txt
     Here s123.txt is the file.

11)Display the list of last 15 files present
 in the current directory.
Ans: [cmsa1@localhost ~]$ find . -maxdepth 1 -type f|tail -15

12)Redirect the sorted output of names of currently
 logged in users to a file.
Ans: [cmsa1@localhost ~]$ who|cut -d " " -f 1|sort|uniq > users1.txt

13) A file contains a word ‘district’ in some lines.
 Redirect those lindes to a file bbb.
Ans: [cmsa1@localhost ~]$ grep -w "district" s1234.txt > bbb

14) Redirect the output of the command
 pwd and date in succession to a file hhh.
Ans: [cmsa1@localhost ~]$ (pwd;date) > res1.txt      
     [cmsa1@localhost ~]$ cat res1.txt  
     /home/cmsa1               
     Thu Sep 12 13:57:07 IST 2016

15) There are 2 text files. Write a command to display the total
 no of words in both the files.
Ans: [cmsa1@localhost ~]$ cat s1.txt s2.txt | wc –w

16)Move the files p1 and p2 to the directory Dest.
Ans: [cmsa1@localhost ~]$ mv p1.txt p9.txt dest

17) List the content of the 3 files t1 , t2 and t3
 in a single command.
Ans: [cmsa1@localhost ~]$ cat t1.txt t2.txt t3.txt

18) Output the contents of the fields 1 and 3 from a
 text file student where delimeter between fields is ‘:’
Ans: [cmsa1@localhost ~]$ cut -d ':' -f 1,3 s5.txt

19) Find out number of files in a directory.
Ans: [cmsa1@localhost ~]$ find . -maxdepth 1 -type f | wc –l

20)Redirect the number of lines of a file to a file sss.
Ans: [cmsa1@localhost ~]$ cat s1.txt | wc -l > sss

21) List all filenames starting with a or b or s.
Ans: [cmsa1@localhost ~]$ ls [abs]*

22)Report no of lines containing a given number say 60,
 in all files in the current directory.
Ans: [cmsa1@localhost ~]$ grep –w “60” ./* | wc -1

23)List first 10 lines of a given file.
Ans: [cmsa1@localhost ~]$ head -10 mycat.c

24) Create 3 empty files f1 , f2, f3.
Ans: [cmsa1@localhost ~]$ touch f1 f2 f3

25) Create a file with timestamp 15 th august 2012 at 12:40 hours.
Ans: [cmsa1@localhost ~]$ touch -t 1208151240 abc1
     Here abc1 is the name of the file.