a - sed command and options sed command(stream editor) is text processing tool. It can perform basic text transformations on input stream(file or command output) syntax → sed [options] 'script' inputfile script → is the script to be executed by sed common options: -i → Edit files in place (save the changes to the original file) -e script → Add the script to the list of editing commands. This is typically used when you want to specify multiple scripts. -f script_file → Read the editing commands from `script_file`. -n → Suppress automatic printing of pattern space
b - sed common scripts s/what/with → substitute what with with, s = replace s/what/with/3 → substitute the 3rd what with with, 3 = 3rd occurence s/what/with/3h → substitute the 3rd what with with and all others after the 3rd s/what/with/g → substitute what with with all occurences, g = global 3 s/what/with/ → substitute what with with on line 3, 3 = line 3 n,md → deletes lines from n to m line, d = delete n a\ newline → appends newline after line n, a=append /pattern/p → prints lines containing specific pattern
c - sed examples sed -n '=;p' example.txt prints line numbers sed 's/This/That/g' example.txt replaces This with That sed '/This/d' example.txt deletes all This sed -e 's/This/That/g' -e 's/And/---/' example.txt replace multiple patterns echo "s/This/That/g" scriptFile create a script file sed -f scriptFile example.txt use a script file sed -s 's/This/That/g' example.txt example1.txt replaces This with That in 2 files