Date: Mon, 26 Jul 93 09:11:46 -0400
From: DJ Delorie <dj AT ctron DOT com>
To: chan AT turing DOT scs DOT carleton DOT ca
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: Re: page

fseek is capable of seeking relative to the current position:

skip_backward(int file, int amount)
{
  fseek(file, -amount, 1);
}

Zero says from the begining, one is from current, two is from end.
Negative amounts mean backward.