I have a stock of functions which are sourced from /etc/profile.local. Associative array as return value. on April 28, 2010. Associative arrays always carry the -A attribute, and unlike indexed arrays, Bash requires that they always be declared explicitly (as indexed arrays are the default, see declaration). Arrays. If you agree with that, then you probably won't want to read about the "new" associative arrays that were added in version 4.0 of bash. How associative array can be declared and accessed in bash are explained in this tutorial. I can create an associative array by calling a function, but the array is not available outside the creative function. Other details: Machine: x86_64 OS: linux-gnu Compiler: gcc Compilation CFLAGS: -DPROGRAM='bash' -DCONF_HOSTTYPE='x86_64' -DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='x86_64-pc-linux-gn$ uname output: Linux ubuntu … Posted by 22 days ago. What specifically is your concern about the script being "easily modified" here? I am trying to assign indexes to an associative array in a for loop but I have to use an eval command to make it work, this doesn't seem correct I don't have to do this with regular arrays For example, the following assignment fails without the eval command: #! Then enter the following command to check your installed version of bash: $ bash--version. After executing unset against the entire array, when trying to print its content an empty result is returned: the array doesn't exist anymore. The bash man page has long had the following bug listed: "It's too big and too slow" (at the very bottom of the man page). Example: Here array_keys() function is used to find indices names given to them and count() function is used to count number of indices in associative arrays. So, if you want to return something, you should use global variables that are updated inside your function. This feature is added in bash 4. Moreover the associative array export file was created using one of these functions. Bash Associative Arrays by Mitch Frazier. There are the associative arrays and integer-indexed arrays. So far, you have used a limited number of variables in your bash script, you have created few variables to hold one or two filenames and usernames.. You can get the value from bash functions in different ways. The return command is not necessary when the return value is that of the last command executed. Returning a variable from functions in bash script can be little tricky. Hi all, I am trying to create a function that return an array of integer based on the char parameter pass into the function. The best solution probably is, as already been pointed out, to iterate through the array and copy it step by step. You can only use the declare built-in command with the uppercase “-A” option.The += operator allows you to append one or multiple key/value to an associative Bash array. My current bash version is 5.0.3 so I am good to go. How to return a value from bash function; Iterate over specific file extension in a dir in shell script; Linux - Yesterday's Date in YYYYMMDD format ; bash - extract urls from xml sitemap; bash - how to use regex in if condition . func_a(char * str) { example str is equal to "1,2,3,4" return an array of integers of 1,2,3,4 } Please advise regards dwgi32 (2 Replies) First by using for loop and secondly by using foreach. 0,1 doesn't mean anything special in associative arrays, that's just the string 0,1. It is important to remember that a string holds just one element. Copying associative arrays is not directly possible in bash. Unlike in many other programming languages, in bash, an array is not a collection of similar elements. Return Values. Bash functions, unlike functions in most programming languages do not allow you to return a value to the caller. In Bash, there are two types of arrays. Example. Bash seems to silently execute a function return upon the second declare statement. Does your .bash_functions source .bash_functions.test from within a function by any chance? Check the current version of Bash before starting the next part of this tutorial. For the record, in zsh, to turn two arrays into an associative array/hash, you'd do: typeset -A hash hash=("${(@)array1:^array2}") Where ${array1:^array2} is the array zipping operator and the @ parameter expansion flag is used to preserve empty elements (in double quotes, similar to "$@"). (by the way, bash hashes don't support empty keys). The return command terminates the function. You could use the same technique for copying associative arrays: But what if you need more than few variables in your bash scripts; let’s say you want to create a bash script that reads a hundred different input from a user, are you going to create 100 variables? associative arrays. If you retrieve multiple values from the array at once, you can't count on them coming out in the same order you put them in. Most other programming languages have the concept of a return value for functions, a means for the function to send data back to the original calling location. User account menu. Run the following command from the terminal to check the installed version of bash. Associative Array: Associative arrays are used to store key-value pairs. Press question mark to learn the rest of the keyboard shortcuts . With bash, the syntax is the same awkward one as in ksh93: array=([key1]=value1 [key2]=value2), so you cannot easily get the output of a command into an associative array other than by using a loop doing one single element assignment at a time as others have shown. You should do a minimal search in google, because this was the first link returned for "bash return array" Edit: In bash, functions don't return values. 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