Tutorial

Arguments can be passed to the script when it is executed, by writing them as a space-delimited list following the script file name.

Inside the script, the $1 variable references the first argument in the command line, $2 the second argument and so forth. The variable $0 references to the current script. In the following example, the script name is followed by 6 arguments.

Example

my_shopping.sh file contains below code.

#!/bin/bash
echo "File name is "$0 # holds the current script
echo $3 # $3 holds banana
Data=$5
echo "A $Data costs just $6."
echo $#

Executing the script on terminal as,

bash my_shopping.sh apple 5 banana 8 "Fruit Basket" 15

output is

File name is my_shopping.sh

banana

A Fruit Basket costs just 15

6

The variable $# holds the number of arguments passed to the script

The variable $@ holds a space delimited string of all arguments passed to the script

Exercise

Pass "Shell is fun" (3 arguments) to the script(prog.sh) as an arguments and print the length of the arguments.

Tutorial Code

#!/bin/bash
function File {
    # think you are inside the file
    # Change here
    echo "print the arguments"
}

# Do not change anything
if [ ! $# -lt 1 ]; then
    File $*
    exit 0
fi

# change here
# here you can pass the arguments
bash test.sh arguments

Solution

#!/bin/bash
function File {
    # think you are inside the file
    # Change Here
    echo $#
}

# Do not change anything
if [ ! $# -lt 1 ]; then
    File $*
    exit 0
fi

# change here
# here you can pass the arguments
bash prog.sh Shell is fun

Expected Output

3