What would be the condition to check whether file with name "xyz" is a regular file?

Which statement is incorrect regarding if-then-fi?

If x=11 and y=6, then what is the exit status of the following expression?

Which expression is correct?

Output of the following program assuming that the command line arguments are dog parrot cuckoo? for argument in $* do echo $argument done

Which of the following is true about the 'continue' statement?

What is the error in the following program?

Which is correct declaration(s) of a null variable 'a' in shell script?

A shell script is executed by:

Which statement is true?

On executing the statement: set -3 + 1