Bash Check If String Contains Substring Code Example


Example 1: checking if a substring exists in a string bash

string='Haystack';  if [[ $string =~ "Needle" ]] then    echo "It's there!" fi

Example 2: bash substring test

#!/bin/bash  STR='GNU/Linux is an operating system' SUB='Linux'  if grep -q "$SUB" <<< "$STR"; then   echo "It's there" fi

Example 3: bash substring test

#!/bin/bash  STR='GNU/Linux is an operating system' SUB='Linux'  case $STR in    *"$SUB"*)     echo -n "It's there."     ;; esac

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