Change how print behaves in printing.el

[Shiyuan]

Hi all,

   I am using printing.el package. Normally, when I hit the print in the printing interface,  the printer will print the document. But I want to change this so that when I print, it will also leave a pdf copy of the document in the specified directory. Right now, I can do it in three steps, first use the postscript printer to print it to a .ps file, and then print the ps file from command line and convert the .ps file to .pdf file using ps2pdf. I am wondering can I write this into a emacs function/script, and ask printing.el to call this function every time I hit print in the printing interface? Thank you.