From man bash: return [n] Causes a function to stop executing and return the value specified by n to its caller. The bash supports two structures for functions. which means exiting in the Bash function, only exits from that shell - which makes sense but I didn’t know that. Every Linux or Unix command executed by the shell script or user, has an exit status. In other words, you can return from a function with an exit status. Option: return –help: It displays help information. It takes a parameter [N], if N is mentioned then it returns [N] and if N is not mentioned then it returns the status of the last command executed within the function or script. Also, I'm pretty sure you don't want to return failure for the first line that doesn't match, just if no line matched: More on Linux bash shell exit status codes. that's something very different. return command is used to exit from a shell function. A non-zero (1-255) exit status … Creating Functions. The return command causes a function to exit with the return value specified by N and syntax is: return N The exit status is an integer number. is used to display the last return status. Don’t … You don’t put parentheses around the arguments like you might expect from some programming languages. The bash if command is a compound command that tests the return value of a test or command ($?) In using the first syntax, you have to use the keyword function, followed by your function name and open and close parentheses and curly braces to separate the contents of your functions to your main routine. For the bash shell’s purposes, a command which exits with a zero (0) exit status has succeeded. In computer a shell function name can take an input, $1 and return back the value (true or false) to the script. It turns out when you cal a Bash function using the syntax $() you are actually invoking a subshell (duh!) That means, the original issue I sought out to fix wouldn’t actually be fixed. true and false are commands that exit with success and failure exit codes, respectively. If a numeric argument is given to return, that is the function’s return status; otherwise the function’s return status is the exit status of the last command executed before the return. Syntax: return [N] Example: Note: echo $? #5 building As mentioned earlier, the "correct" way to return a string from a function is to replace it with a command. There is a simple, useful idiom to make your bash scripts more robust - ensuring they always perform necessary cleanup operations, even when something unexpected goes wrong. what you said was to put my code in a function. Bash function and exiting early 2019-10-18. indeed that works in my test script (2 files, 1st an ordinary script that sources the 2nd) and test command (just sourcing the 2nd file) on my version of bash (4.4.20 on Ubuntu 18.04 LTS). Variables local to the function may be declared with the local builtin. Early return if there is some obvious dead end condition to check for right away that would make running the rest of the function pointless. Although the tests above returned only 0 or 1 values, commands may return other values. … If return is used outside a function, but during execution of a script by the . The secret sauce is a pseudo-signal provided by bash, called EXIT, that you can trap ; commands or functions trapped on it will execute when the script exits for any reason. * Set Retval + single return if the function is more complex and could have multiple exit points otherwise (readability issue). If n is omitted, the return status is that of the last command executed in the function body. *This can often indicate a design problem. Syntax. and branches based on whether it is True (0) or False (not 0). 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