1. Which of the following is a valid variable assignment?
- MY VAR= “set to one”
2. Shell variables are case insensitive.. True or False?
3. Which of the following is NOT a valid variable name?
4. A new environment variable can be “exported” and assigned a value with a single command.. True or False?
5. Which of the following is NOT a valid command for variable declaration?
- typeset –x ENV_VAR=1
- export ENV_VAR=1
- newvar –x ENV_VAR=1
- declare –x ENV_VAR=1
6. The ___________ command is used to display the value of a specific variable.
7. Which command can be used to display both local and environment variables?
- export –p
- declare –x
8. A variable once declared cannot be deleted.. True or False?
9. Which command can be used to delete a variable?
- set -r
10. PATH variable directories are searched __________ when executing a command.
- Left to right
- Right to left
- In no particular order
- Including only the first 256 characters
11. Which of the following is NOT a valid option for executing a command that is not in the directories listed in the PATH variable?
- By typing the absolute or relative path to the command
- Rename the command and its directory
- Add the directory containing the command to the PATH variable
- Copy the command to a directory listed in the PATH
12. The command PATH=$PATH:/home/John does the following:
- Creates a new PATH variable with only the /home/John directory as the value
- Does nothing, because anything after the : is discarded
- Appends the directory /home/John to the existing PATH variable
- Replaces the existing directories in the PATH with the /home/John directory
13. Consider the following value of PATH variable: /bin:/usr/local/sbin:/home/joe/bin:/home/joe/test Joe modifies the my_scr.sh script, which is stored in the directory /home/joe/bin then places a copy of my_scr.sh in /home/joe/test. Executing my_scr.sh will:
- Run the original version of the script in the /home/joe/bin directory
- Check the timestamp and run the latest version of my_scr.sh
- Not run at all, reports error
- Run the new version of the script placed in /home/joe/test
14. The ___________ command can be used to check if the command already exists.
15. Which of the following switches will include the full path in the prompt?
16. Defining the PS1 variable in an initialization file will make changes to the prompt persistent between logins.. True or False?
17. If the command HISTIGNORE=’ls*’ is placed in the ~/.bash_profile file, which of the following commands would not be placed in the history list?
18. Which of the following is NOT a purpose for creating an alias?
- To create a short nickname for a long command or series of commands
- To create “DOS-like” commands
- To make them run faster
- To include a command option by default
19. The command to remove an existing alias from the current shell is:
- alias –d
- unset alias
20. The best way to group multiple commands and pass arguments is to:
- Create an alias
- Concatenate them
- Use functions
- Create an initialization file
21. A function accepts 3 arguments as input. The third argument of a function is identified as:
22. Changes in the __________ initialization file will affect all the users on the system.
23. Local initialization files, by default, are stored in which directory?
- User’s home directory
24. A Login BASH shell executes which of the following additional files (compared to an interactive BASH shell)?
- /etc/profile and /etc/bashrc
- /etc/profile and ~/.bashrc
- /etc/profile and either ~/.bash_profile or ~/.bash_login or ~/.profile
- ~/.bash_profile and ~/.bashrc
25. Administrators use the __________ file to create key environment variables and set key system values for every user.
26. Sourcing is an effective way to test initialization file changes. Which of the following is used to source a file?
- touch command
- ~ character
- Either . character or the source command
- None of the above
27. Which script is executed when you exit the shell?
28. Typical BASH exit scripts are found in ~/.bash_logout and __________ files.
29. Most of the Linux commands used by regular users can be found in which directory?