multiple files opened in awk

Hi ,
i' d like to use an awk script to automate the ripping of cds : here's how it works :

  • i first create a file named songs.txt containing the name of the songs
  • the scripts extracts the tracks of a cd with cdparanoia
  • the scripts saves the contents of the dir with ls (ls > list.txt)
  • the scripts rename each filename contained in list.txt by its equivalent in songs.txt

i don't know how to do the last step , because it implies to have multiple files opened at the same time ...

do you know how to do it?