linux replace text in file code example

Example 1: ubuntu command line replace word in files

sed -i 's/original/new/g' file.txt

Example 2: linux replace string in all files

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

Example 3: replace word in file linux command

sed -i 's_oldword_replaceword_gI' document_name.txt