Question

Post-Lab 2: GNU and UNIX commands Keywords: • Sort • head tail • Pipe (D • Redirection ) • alias • Wildcards • Metacharcters . sed utility Find • tar 1. Create a directory called Dirl and if the creation was successful, change the current working directory to be Dirl. 2. Extract lines 3-5 from a file, first using head to get the first 5 lines then tail to get the last 2 lines . With pipes . With redirection 3. Create a redundant filename.txt and leave some lines as blank. Implement the following tasks on it using sed utility: A. Remove the 3rd line from a file. B. Delete all occurrences of a "line" in the file C. List all non blank lines. (using sed command) 4. Write an alias named REMOVE that asks the user to confirm deleting any file before deleting it..

Answer 1

Answer:

1. To create a directory- mkdir dir1 ( we use this command to create a directory in unix)

To change a directory- cd dir1 ( this command is used to change a directory in unix)

2- With pipelines- head -5 hello1.txt | tail -3 (this command will extract lines from 3rd to 5th)

head -5 hello1.txt (this command will display starting 5lines of a file.)

tail -3 hello1.txt (this command will display last 3lines of a file.)

With redirection-

head -5 hello1.txt >sample.txt (this command will redirect lines in sample.txt file)

Tail -1 hello1.txt >sample.txt

3- cp my.txt hello2.txt (this command will create a redundant file of my.txt)

sed 3d  hello2.txt (this command will delete 3rd line of a file)

sed ‘/is/d’ hello2.txt (this command will delete occurrence of is in a file)

sed ‘/^$/D’ hello2.txt (this command will display non-blank lines of a file.)

4- To delete a file type command - rm hello2.txt (after enter press it will prompt type 'Y' to remove or type 'N' not remove.

This is my file content. head and tail commands used separately.

[root@localhost ~]# ls dos hello. c hello1.txt [root@localhost.~]# cat hello1.txt unix is an operating system. it is very easy to learn. linux is also an operating system. it is open source. it is very secure and freindly to use. most of the people use linus. unix is not too freindly. it is complex and tough to Us we should learn both operating systems. [root@localhost ~]# head -3 hello1.txt unix is an operating system. it is very easy to learn. linux is also an operating system. [root@localhost # tail -2 hello1.txt it is complex and tough to use. we should learn both operating systems.

head and tail command used with pipeline

rootalocalhost 15 dirldos hello.c hello1.txt [root@localhost ~]# cat hello1.txt unix is an operating system. it is very easy to learn. linux is also an operating system. it is open source. it is very secure and freindly to use. most of the people use linus. unix is not too freindly... it is complex and tough use." we should learn both operating systems. [root@localhost ~]# [root@localhost ~]# head -5 hello1.txt tail -3 linux is also an operating system. it is open source. it is very secure and freindly to use. [root@localhost ~]# .

head and tail commands used with redirection.

[root@localhost ms] # root@localhost # head -5 hell01.txt tail -3 Rinux is also an operating system. it is open source. it is very secure and freindly to use. [root@localhost' -# head -3 sample.txt, Troot@localhost # [root@localhost w head -3 he1101.txt sample.txt [root@localhost cat sample.OXU unix is an operating system. it is very easy to learn. linux is also an operating system. [root@localhost # tail -2 hell01.txt >sample1.txt [root@localhost # cat sample1.txt it is complex and tough to use. we should learn both operating systems. [root@localhost -# Paste Here Fabnice Belle Ne

sed command to delete a specific line.

Susah ww [root@localhost ~]# sed d hell01.txt unix is an operating s it is very easy to learn. it is open source. it is very secure and freindly to use. most of the people use linus. unix is not too freindly. it is complex and tough to use. we should learn both operating systems. [root@localhost ~]#