Knowing how to modify files at the command line is an essential skill for any Linux administrator. This learning activity will focus on using the Vim text editor to practice creating a new file, adding text to the file, and then modifying that text. We will also practice some of the basic keyboard shortcuts to change the text of this file.
Successfully complete this lab by achieving the following learning objectives:
- Create a new file
Using the vim text editor, create a new file called notes.txt in the cloud_user home directory. Enter the text "Beginning of Notes File" at the top of the document. Leave two blank lines under this top line. Save and close the file.
The process is:
vi notes.txt i (insert) Text - Beginning of Notes File (2 blank lines) :wq!
- Send Data to the notes.txt file
catcommand and output redirection, send the contents of the /etc/redhat-release file to the end of the notes.txt file, taking care to append the contents so as to not overwrite the file.
This can be accomplished via:
cat /etc/redhat-release >> notes.txt
- Modify the notes.txt File
Open the notes.txt file for editing again. Place the cursor before the openening parentheses around the word "Core." Using a keyboard shortcut, delete the text from the cursor position to the end of the line. Leave two blank lines under this line. Save and close the file.
The following process will meet the criteria:
vim notes.txt (cursor to 'core') SHIFT D (or d$) remove cursor to end of line o - blank line enter (2nd line) :wq!
- Send More Data to the File, and Modify Its Contents
free -mcommand and output redirection, send the output of the command to the end of the notes.txt file, taking care to append the contents so as to not overwrite the file.
Open notes.txt for editing. Move the cursor to the line that begins with "Swap." Using a keyboard shortcut, delete this entire line. Leave two blank lines after the line that begins with "Mem".
Follow this process:
free -m >> notes.txt vim notes.txt move cursor to Swap line dd (delete line) o - blank line enter (2nd) SHIFT: 3 (3rd line of file) i - insert enter (blank line) :wq!
- Enter New Text into the File
Using a keyboard shortcut, jump to line 3 of the file, then enter the text: "This is a practice system." Leave a blank line after this text has been entered. Save and close the file.
You can accomplish this via:
vim notes.txt SHIFT: 3 (moves to 3rd line) i (insert) This is a practice system (enter for blank line) :wq!
- Finalize the Notes File
dbus-uuidgen --getcommand, send the output of this command (which will retrieve the system’s dbus unique ID) to the end of the notes.txt file. Take care to append the contents so as to not overwrite the file. Open notes.txt in vim, and use a keyboard shortcut to jump to the end of the file. At the beginning of the line that contains the dbus ID, enter in the following text: "Dbus ID = " so that there is a space between the equal sign and the Dbus ID number. Save and close the file. Hand the system over for grading.
dbus-uuidgen --get >> notes.txt vim notes.txt SHIFT G (end of file) i - insert Dbus ID = (before ID) :wq!