Showing posts with label UNIX education. Show all posts
Showing posts with label UNIX education. Show all posts

Thursday, April 4, 2019

Unix System Shutdown Commands


The common ways to shut down a Unix system properly via the command line is as such:

halt - takes system down right away
init 0 - powers off the system using system scripts
init 6 - reboots the system completely
poweroff - shuts down system by powering it off
reboot - reboots system
shutdown -  shuts down system

Tuesday, March 26, 2019

The UNIX Programmer - Part 1



The following are some fun UNIX exercises to utilize to sharpen your skill set.

The boss has asked you to show your new UNIX intern how to format a report in the following manner – since these are the kinds of reports the intern will be creating all summer long:

1) Output the word count of a report1 then append it to the existing report2:

            Answer: wc –l report1 >> report2
 

2) Using awk show how to extract column 5 (the file size) from the output of ls -l

            Answer: ls –l | awk ‘{print $5}’
 

3) Using sed show how to substitute a change in words globally taking the input from a file

            Answer: sed –e ‘s/platform/computer/g’ < file.txt


4) Using tr convert a file from uppercase to lowercase

            Answer: tr ‘A-Z’ ‘a-z’ < file.txt

 
5) Using grep to search for text in a file at the beginning of a line that starts with the word the

            Answer: grep ‘^The’ the.sh

 
6) Using grep to search for text in a file at the end of a line with the word of

            Answer: grep ‘of$’ the.sh
 

7) Use grep to search for a dollar sign in a file 

            Answer: grep ‘.$’ the.sh