Shell scripting is a fundamental skill that helps system administrators and developers to streamline tasks. It helps them effectively manage systems and handle files efficiently within a command-line environment. This skill is vital for technical interviews in the IT and development fields. So, here are some shell scripting interview questions, that will prepare you well for your interviews and enhance your proficiency.
Here are the 31 most commonly asked interview questions on shell scripting.
Ans. A shell script is a script written for a shell, or command-line interpreter, typically for automating administrative tasks and system management.
Ans. Shell scripting automates administrative tasks and system processes, while programming focuses on creating applications with complex logic.
Ans. Single square brackets `[ ]` are a POSIX compliant test command, while double square brackets `[[ ]]` are an enhanced version with additional features such as pattern matching and string manipulation.
Ans. Multiple lines can be commented out by enclosing them between `: ‘` and `’`, or `<<COMMENT … COMMENT`.
Ans. The `chmod` command changes the permissions of a file or directory, allowing or denying specific users’ read, write, and execute permissions.
Ans. Arguments can be passed to a shell script by listing them after the script name when executing it, for example, `./script.sh arg1 arg2`.
Ans. The shebang line, found at the script’s beginning, identifies the script interpreter’s path and is used to run the script.
Ans. Linux provides three standard streams: Standard Input, Standard Output, and Standard Error.
Ans. The command tput can be used instead of echo, giving control over output display formatting on the screen.
Ans. GUI scripting involves using a graphical user interface to manage computer operations and applications, relying on the operating system for support.
Ans. Shell variables are fundamental in shell scripts, enabling the storage and manipulation of data, typically stored as string variables.
Ans. Shell scripting has several drawbacks: it starts slowly but speeds up, is not easily portable, can cause data loss due to typing errors, and poor designs can be costly and disruptive.
Ans. Crontab, or cron table, refers to a list of scheduled commands managed by the cron job scheduler, used to execute tasks at regular intervals.
Ans. A Linux process has four stages: Waiting (for resources), Running (currently executing), Stopped (post-execution), and Zombie (active in process table but stopped).
Ans. Metacharacters are special characters in a shell that provide information about other characters. For instance, using ls s* lists all files starting with ‘s’.
Ans. Use the isql utility, included with the open client driver, to connect to a database server:
isql –S serverName –U username –P password
Ans. A superblock contains vital records of a specific file system, such as size, counts of filled and empty blocks, usage information, block groups’ size, and inode tables’ location and size.
Ans. A shell is a command-line interpreter that converts user-entered commands into a form understandable by the kernel, executing the required programs.
Ans. The ‘$#’ variable displays the total number of arguments passed to a script.
Ans. $* treats all positional arguments as a single string, whereas $@ treats each quoted argument separately.
Ans. Common Linux shells include the C-Shell (e.g., TENEX C-Shell, Z-Shell) and Bourne Shell (e.g., Korn Shell, POSIX Shell, Bourne-Again Shell).
Ans. Yes, though there may be differences in shell syntax and commands across systems.
Ans. In UNIX, multiple shells can exist, but there is only a single kernel.
Ans. Use the >> operator to append output to a file. Example: echo "text" >> file.txt.
Ans. Special variables include $0 (script name), $# (number of arguments), $* (all arguments), and $@ (all arguments as separate strings).
Ans. Enable debugging with the -x option, which prints each command before execution. Example: bash -x scriptname.sh.
Ans. awk is a powerful text processing and data extraction language used within scripts.
Ans. Use the sed command to find and replace text. Example: sed 's/oldtext/newtext/g' file.txt.
Ans. The eval command executes arguments as a shell command.
Ans. Automating backups, system monitoring, batch file processing, and user account management.
Ans. Use meaningful variable names, add comments for clarity, handle errors, and avoid hard-coding values.
One skill that greatly increases the productivity of both developers and system administrators is shell scripting. It guarantees efficient system administration, streamlines processes, and manipulates files with skill via command-line interfaces. Technical interviews in the IT and development domains require proficiency in this area. Knowing these 31 crucial shell scripting interview questions will help you prepare, increasing your preparedness and shell scripting proficiency.
I'm a tech enthusiast, graduated from Vellore Institute of Technology. I'm working as a Data Science Trainee right now. I am very much interested in Deep Learning and Generative AI.
Lorem ipsum dolor sit amet, consectetur adipiscing elit,
