Computer Science - Unix - Discussion

Discussion :: Unix - Section 1 (Q.No.28)

28. 

Which of the following special shell variables is used to process number of the last background job?

[A]. $!
[B]. $#
[C]. $0
[D]. $*
[E]. None of the above

Answer: Option A

Explanation:

No answer description available for this question.

Dharmajit said: (Sep 21, 2014)  
$0 The filename of the current script.

$n These variables correspond to the arguments with which a script was invoked. Here n is a positive decimal number corresponding to the position of an argument (the first argument is $1, the second argument is $2, and so on).

$# The number of arguments supplied to a script.

$* All the arguments are double quoted. If a script receives two arguments, $* is equivalent to $1 $2.

$@ All the arguments are individually double quoted. If a script receives two arguments, $@ is equivalent to $1 $2.

$? The exit status of the last command executed.

$$ The process number of the current shell. For shell scripts, this is the process ID under which they are executing.

$! The process number of the last background command.

Sruthi said: (Dec 14, 2015)  
I think $0 displays current shell.

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