We also have an option to pass input arguments to the bash function. after having the functions above the case it worked, but if I give the two options at a time only the first option is working!!! Bash Functions. Here’s how to call a function in Bash, with or without arguments. Call bash function with arguments. In the subscripts or functions, the $1 and $2 will represent the parameters, passed to the functions, as internal (local) variables for this subscripts. (Or if you want to lock yourself to exactly three arguments, $1 to $3.) Create a bash file and add the following script to understand the use of getopts function. You can use $1, $2, $3 and so on to access the arguments inside the function. Don’t … badUsage "Option/command not recognized." case statement is used … badUsage Then there is the function for … Passing inputs to a function is no different from passing arguments to a Bash script: function simple_inputs() { echo "This is the first argument [$1]" echo "This is the second argument [$2]" echo "Calling function with $# arguments" } simple_inputs one 'two three' Let’s take a … $1 only contains one of them, in both Bash and Zsh. Note: for arguments more than 9 $10 won't work (bash will read it as $10), you need to do ${10}, ${11} and so on. abc "$@" When using $@, you should (almost) always put it in double-quotes to avoid misparsing of arguments containing spaces or wildcards (see below).This works for multiple arguments. Why would you need that you ask? The function badUsage may or may not make an argument. Here is an example. You don’t put parentheses around the arguments like you might expect from some programming languages. The scope of a local variable limited to function while you can access global variables out of function. You can pass arguments to the bash function easily by writing them with double quotes after function name separated by space. 2 - 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. So now about arguments with bash functions. Passing Arguments in Bash Functions. It is also portable to all POSIX-compliant shells. Put any parameters for a bash function right after the function’s name, separated by whitespace, just like you were invoking any shell script or command. Function has to be defined in the shell script first, before you can use it. This is a while loop that uses the getopts function and a so-called optstring—in this case u:d:p:f:—to iterate through the arguments. To pass all the arguments on, you have to use $@. Here, 4 options are used which are ‘i’, ‘n’, ‘m’ and ‘e’ . ‘getopts’ function is used with while loop to read command line argument options and argument values. Imagine you are trying to write a function to compare two integers but these integers will be provided by end user as command line argument; So how will function access these integer values for comparison? Arguments could be passed to functions and accessed inside the function as $1, $2 etc. You should use getopt or getopts for processing options. The $@ variable expands to all command-line parameters separated by spaces. – kashyap Apr 24 '17 at 21:57 @kashyap case doesn't loop. Each bash function has its own set of positioned arguments just like that of the main script file. If an argument is passed to the function, it is printed as a message. When I do to call the function I just need to pass the values that I want for $1 $2 and so forth. 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