Important Unix Shell Questions
Some Important Unix Shell Questions for Recent Graduates to help them in their Interview Preparations.
- There can be multiple Kernels and shells running on your system. True or False?
- Why shell is called Command Interpreter?
- Two UNIX systems may or may not use the same system calls. True or False?
- To obtain help on any feature of the system, what are the possible help sources available?
- Why are the directories /bin and /usr/bin usually found first in the output of echo $PATH?
- If two commands with the same filename exist in two directories in PATH, how can they be executed.
- How is the Current directory is indicated in the value of the PATH?
- Use the type command with the following arguments—cd, date, pwd and ls. Which are the internal commands in the list?
- What is the difference between an argument and an option?
- if the command ls –all works on your system, which flavor of UNIX could you be using?
- What does the secondary prompt look like and when does it appear?
- You located the string crontab in a man page by searching with /crontab [Enter]. How do you find out the other occurrences of this string in the page?
- What is a pager? Name the two standard pagers used by man.
- If a command doesn’t seem to complete, which key will you press to interrupt it?
- Do you need to wait for a command to finish before entering the next one?
- What do the | and the three dots in the SYNOPSIS section of these man pages indicate as shown below?
/usr/xpg4/bin/tail [ -f | -r ]
/usr/bin/ls [ -aAbcCdfFgilLmnopqrRstux1 ] [file .. ]
- How do you direct man to use a specific pager, say less?
- What is a whitespace? Explain the treatment the shell metes out to a command that contains a lot of whitespace.
- A Program file named foo exists in the current directory, but when we try to execute it by entering foo, we see the message foo: command not found. Explain how that can happen?
- What do multiprogramming, multiuser and multitasking mean?
- Why are many UNIX commands designed to perform simple rather than complex tasks?