In-place edit with backup

More sed commands

• Delete matching lines
  sed '/^#/d' config.txtcopy

  Delete all comment lines starting with #

• Delete blank lines
  sed '/^[[:space:]]*$/d' file.txtcopy

  Remove all empty or whitespace-only lines

• Print specific line numbers
  sed -n '10,20p' file.txtcopy

  Print lines 10 through 20 only (suppress default output with -n)

• Print lines matching pattern
  sed -n '/ERROR/p' app.logcopy

  Print only lines that match ERROR

• Insert line before match
  sed '/^server_name/i # Added by deploy script' nginx.confcopy

  Insert a comment line before every server_name directive

all 15 sed commands →