I solved this just cleaning/declaring the statusCheck associative array … However, I find that things like: I am writing a bash script on CentOS 7.5 that will execute some MongoDB commands. Associative arrays are like traditional arrays except they uses strings as their indexes rather than numbers. An associative array lets you create lists of key and value pairs, instead of just numbered values. Example 1: Bash Array. One of these commands will set replication servers. If you are familiar with Perl, C, or Java, you might think that Bash would use commas to separate array elements, however this is not the case; instead, Bash uses spaces: I will mention the shell used before each example. Bash Shell Script Let’s create an array that contains name of the popular Linux distributions: distros=( Play my Android game Rabbit Escape! A few Bourne-like shells support associative arrays: ksh93 (since 1993), zsh (since 1998), bash (since 2009), though with some differences in behaviour between the 3. In bash, array is created automatically when a variable is used in the format like, name[index]=value. Example. 1. Declaring an Array and Assigning values. No problem with bash 4.3.39 where appenging an existent key means to substisture the actuale value if already present. So for example after some repetion the content of the value was "checkKOcheckKOallCheckOK" and this was not good. List Assignment. There are at least 2 ways to get the keys from an associative array of Bash. Update: see also Bash Arrays. Bash, however, includes the ability to create associative arrays, and it treats these arrays the same as any other array. Following is an example Bash Script in which we shall create an array names, initialize it, access elements of it and display all the elements of it. Examples. A common use is for counting occurrences of some strings. Bash associative array examples. Bash, however, includes the ability to create associative arrays, and it treats these arrays the same as any other array. Bash: declare -A MYARRAY Ksh: typeset -A MYARRAY Array with values. Declare an associative array Empty array. Share on Mastodon Quick reference of things I discovered about how to use associative arrays in bash. 1. In some programming languages, arrays has to be declared, so that memory will be allocated for the arrays. Also, array indexes are typically integer, like array[1],array[2] etc., Awk Associative Array. Let’s start with an example associative array: $ declare -A aa $ aa["foo"]=bar $ aa["a b"]=c. Note: bash version 4 only. I have this associative array that is the hostname an IPs of servers (I used an associative array because other parts of code needed it). Enough with the syntax and details, let’s see bash arrays in action with the help of these example scripts. 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