[string] Replace whole line containing a string using Sed

for manipulation of config files

i came up with this solution inspired by skensell answer

configLine [searchPattern] [replaceLine] [filePath]

it will:

  • create the file if not exists
  • replace the whole line (all lines) where searchPattern matched
  • add replaceLine on the end of the file if pattern was not found

Function:

function configLine {
  local OLD_LINE_PATTERN=$1; shift
  local NEW_LINE=$1; shift
  local FILE=$1
  local NEW=$(echo "${NEW_LINE}" | sed 's/\//\\\//g')
  touch "${FILE}"
  sed -i '/'"${OLD_LINE_PATTERN}"'/{s/.*/'"${NEW}"'/;h};${x;/./{x;q100};x}' "${FILE}"
  if [[ $? -ne 100 ]] && [[ ${NEW_LINE} != '' ]]
  then
    echo "${NEW_LINE}" >> "${FILE}"
  fi
}

the crazy exit status magic comes from https://stackoverflow.com/a/12145797/1262663

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