getopts is a function where it can be used to read specified named parameters and set into the bash variables in a easy way. test.sh #!/usr/bin/env bash if [ $# -ge 3 ] then echo script has at least 3 arguments fi produces the following output (Or if you want to lock yourself to exactly three arguments, $1 to $3.) We also have an option to pass input arguments to the bash function. You can pass more than one argument to your bash script. # the remaining script arguments can be passed to this function. Here is a possible solution that allows you to call a specific function in the script: $ cat functions.sh #!/bin/bash ls2() { echo "Hello World" } ls3() { echo "Testing $*" } # the next line calls the function passed as the first parameter to the script. Passing multiple arguments to a bash shell script. Bash provides different functions to make reading bash input parameters. Arguments could be passed to functions and accessed inside the function as $1, $2 etc. This function, prints the first argument it receives. Passing Arguments in Bash Functions. Bash Functions – In this Bash Tutorial, we shall learn about functions in Bash Shell Scripting with the help of syntax and examples.. About Bash Functions. You can also put arguments without double quotes but in case of spaces used inside the argument, you should use double-quotes. $1 only contains one of them, in both Bash and Zsh. Write a Bash script so that it receives arguments that are specified when the script is called from the command line. If you'd like to check if the argument exists, you can check if the # of arguments is greater than or equal to your target argument number. Functions receives arguments to $1,$2… etc. The following script demonstrates how this works. Bash – Function with Argument. 8.2 Functions with parameters sample #!/bin/bash function quit { exit } function e { echo $1 } e Hello e World quit echo foo This script is almost identically to the previous one. #2. getopst will read every input parameter and look for the options to match and if match occrus the parameter value set to given variable name. Chapter 9: Functions from the Linux shell scripting wiki. If you want to pass all but the first arguments, you can first use shift to "consume" the first argument and then pass "$@" to pass the remaining arguments to another command. Create a shell script using following code. Fig.01: Bash function displaying number of arguments passed to foo() See also. Don’t … Bash Functions. In general, here is the syntax of passing multiple arguments to any bash script: script.sh arg1 arg2 arg3 … The second argument will be referenced by the $2 variable, the third argument is referenced by $3, .. etc. You don’t put parentheses around the arguments like you might expect from some programming languages. Use this method when a script has to perform a slightly different function depending on the values of the input parameters, also called arguments. Why would you need that you ask? Call bash function with arguments. The passing argument to functions is similar to pass an argument to command from shell. To pass all the arguments on, you have to use $@. To do the same without quotes, they'd do program -p hello_world -tSu, where the function program itself gets three arguments. You can pass arguments to the bash function easily by writing them with double quotes after function name separated by space. 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