A quick guide on how to create and call functions in Bash. Here are the options available for returning data from a function. If we do not return an exit code, then Bash will return the exit status of the last command in our function. Using Functions: Parameters and Return Values. I want to return a string from the Bash function. Returning function values in bash. I'll write examples in Java to show what I want to do: The following example works in bash, but is there a better way? Bash Function Return Values Like in other programming languages you can return the process value at the end of the function, You can not do such things in bash function. #!/bin/bash function quit { exit } function hello { echo Hello! } I have two scripts. More portable code may use explicit conditional constructs with the same effect: Perhaps the most elegant solution is to keep a global name for the function return value and use it consistently in every function you write. You can use the return builtin command to return an arbitrary number instead. Bash behaves in ways unlike other programming languages. To elaborate, the "return value" is always a number. ;}; o 1. returnsol But you can return status of the function using return statement. As mentioned earlier, the "correct" way to return a string from a function is to replace it with a command. A function may return control to the caller of the function, exit the function, using the bash builtin return command. Functions in Bash Scripting are a great way to reuse code. There are two ways to call functions in bash; the first being statically by the function … The returned values are then stored to the default variable $?For instance, consider the following code: In the example, we pass the parameters int1 and int2 to the add function. `return` beendet die Funktion nicht, wenn es von einer Pipe aufgerufen wird . You can think of it as the exit status of that function. How do you get values back? You can think of it as the exit status of that function. For instance, if your function name is my_func then it can be execute as follows: If any function accepts arguments then those can be provided from command line as follows: Bash functions can: 1. I want to return a string from the Bash function. In the following example, a global variable, 'retval' is used. The code above sets the global variable myresult to the function result. Eliminate repetitive tasks 2. Consider the following code to Vicky Ronnen Look up: Perhaps the normal situation is to use the syntax used in the test? calling functions. But the name itself can still interfere, so if you plan to use a value previously stored in a passed variable and then write a return value in it, note that you must copy it to another local variable from the beginning. If there are none, or there are more than two, the function returns -1. Save time 3. Executing a script without parameters produces, How to return string value from Bash function. With functions, we can You want to use a function and you need to get some values into the function. 16 . Bash functions are named blocks of code that can be reused in scripts. Local variables can be sent because they are dynamically scoped in bash: As others have written, the most direct and reliable solution is to use command substitution: The disadvantage is performance, because it requires a separate process. ;}; o 0 $ o (){echo | while read -r; do return 1; done; echo $? In contrary to other programming languages, Bash doesn’t allow us to return values from the function. The return statement in Bash doesn't return a value like C-functions, instead it exits the function with a return status. Solution. They are particularly useful if you have certain tasks which need to be performed several times. – Michael Dorst Jul 8 '19 at 13:06. add a comment | 4 Answers Active Oldest Votes. Answer . Func function, so in most cases, these two methods can be used, although capturing output is a safer method that can always be used in any case, imitating the return value of the function you return can be found in other languages, as Vicky Ronnen correctly pointed out. The return status can be specified by using the return keyword, and it is assigned to the variable $?. Unlike functions in “real” programming languages, Bash functions don’t allow you to return a value when called. Honestly, it is much simpler than that. Then the value of the sum variable is passed to the main routine through the line retur… 2. Here is sample code to demonstrate it. Articles Related Syntax return [n] If used: inside a Bash functions are not similar to functions in other languages but these are commands. 4. function getSomeString { echo "tadaa" } VARIABLE=$(getSomeString) #1 building. 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