Bash provides some built-in functions such as echo and read, but we can also create our own functions. Aside from creating functions and passing parameters to it, bash functions can pass the values of a function's local variable to the main routine by using the keyword return. I want to return a string from the Bash function. How do you do that? Options. The string (or text) that the command spits out is referred to as its "output", not its "return value". This modified text is an extract of the original Stack Overflow Documentation created by following, The exit code of a function is the exit code of its last command, getopts : smart positional-parameter parsing. I dont want to use the global variables. The return command causes a function to exit with the return value specified by N and syntax is: return N. If N is not specified, the return status is that of the last command. The return status can be specified by using the return keyword, and it is assigned to the variable $?. With functions, we get better modularity and a high degree of code reuse. (5 Replies) Discussion started by: PRKS. 40. Let’s calculate the sum of two numbers: Save time 3. The returnstatement terminates the function. Creating a Function in Bash. 16 . For bash, the concept of functions is more related to the C language concept of functions when functions can return a void type which means that they don't return anything. Problem. Solution. By default, a function returns the exit code from the last executed command inside the function. In the second definition, the brackets are not required. Unlike functions in “real” programming languages, Bash functions don’t allow you to return a value when called. If we do not return an exit code, then Bash will return the exit status of the last command in our function. There are a few options, but my favorite is using Bash’s built-in field separating powers and read command. bash how to return string from function. Eliminate repetitive tasks 2. Answer . I want to know how can we make any function to return string or double value. ;}; o 0 $ o (){echo | while read -r; do return 1; done; echo $? Bash functions are not similar to functions in other languages but these are commands. How do you get values back? This means that a return statement can only signal a numerical exit status with values between 0 and 255. Bash functions can: 1. First option uses passing argument to the function. Bash functions are named blocks of code that can be reused in scripts. Honestly, it is much simpler than that. #!/bin/bash function quit { exit } function hello { echo Hello! } They are particularly useful if you have certain tasks which need to be performed several times. variable. 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. Return Values From Function in Bash. Return is a bash builtin function that causes to update the exit status specified by n. Return is intended to be used only for signaling errors, not for returning the results of function. Like above bstpierre Similarly, I use and recommend explicitly naming output variables: Note the use of quotation marks $. In addition, this only applies to the latest BASH version 4.2. This avoids interpreting $result content as shell special characters. The value returned from the Bash function is the status of the last statement executed in the function. You can think of it as the exit status of that function. 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