Insert rows on specific line in a file

Question

I have opened my existing file in r+ mode.

open(\"#{RAILS_ROOT}/locale/app.pot\", \'r+\') do |f|

end

I want to insert some other rows at specific lin

Answer 1

This has worked for me in the past:

def write_at(fname, at_line, sdat)
  open(fname, 'r+') do |f|
    while (at_line-=1) > 0          # read up to the line you want to write after
      f.readline
    end
    pos = f.pos                     # save your position in the file
    rest = f.read                   # save the rest of the file
    f.seek pos                      # go back to the old position
    f.write sdat                    # write new data
    f.write rest                    # write rest of file
  end
end