SC2206 – ShellCheck Wiki

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Quote to prevent word splitting/globbing, or split robustly with mapfile or read -a.

Problematic code:

array=( $var )

Correct code:

If the variable should be a single element:

array=( "$var" )

If it's multiple lines, each of which should be an element:

# For bash
mapfile -t array <<< "$var"

# For ksh
printf '%s\n' "$var" | while IFS="" read -r line; do array+=("$line"); done

If it's a line with multiple words (separated by spaces, other delimiters can be chosen with IFS), each of which should be an element:

# For bash
IFS=" " read -r -a array <<< "$var"

# For ksh
IFS=" " read -r -A array <<< "$var"


You are expanding a variable unquoted in an array. This will invoke the shell's sloppy word splitting and glob expansion.

Instead, prefer explicitly splitting (or not splitting):

This prevents the shell from doing unwanted splitting and glob expansion, and therefore avoiding problems with data containing spaces or special characters.


If you have already taken care (through setting IFS and set -f) to have word splitting work the way you intend, you can ignore this warning.

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