curses winch() broken?

[Apperson H Johnson]

I have the following code fragment that 
builds a file containing a window in the
curses (i have tried this on SCO XENIX 3.2)

  /* wr is rows, wc is cols */

  for(i=0; i < wr;  ++i) {

  	for (j=0; j < wc;  ++j)  {

	       wmove(w,i,j);

       	       getyx(w,r,c);

  	       fprintf(fp,"%c",winch(w) & 0x0ff);

  	}

  	 fprintf(fp,"\n");

  }


the resulting file under AIX 3.1 on an RS6000
does not contain the same information

has anyone any suggestions ?
(please, I MUST use curses for this one)
thanks,
apperson at brahms.udel.edu