perlknight--

The other solutions are good, but your pseudocode suggests that you're looking for the functions seek() and tell(). Augmenting your pseudocode a little:

if new file
{
   # read all lines and insert into db.

   # Save current position for next time...
   $current_line = tell(FH);
} else if not new file
{
   # Go to current line
   seek(FH,0,$current_line);

   # read all new lines and insert into db

   # Save position for next iteration...
   $current_line = tell(FH);
}
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--roboticus