linux replace all occurrences of string in files code example

Example 1: linux replace string in files recursively

find . -type f -name "*.txt" -exec sed -i'' -e 's/foo/bar/g' {} +

Example 2: linux replace string in all files

sed -i 's/old-text/new-text/g' input.txt

Example 3: sed replace in file

sed -i 's/foo/bar/g' hello.txt