===================================================================
RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/diff3/diff3prog.c,v
retrieving revision 1.20
retrieving revision 1.21
diff -c -r1.20 -r1.21
*** src/usr.bin/diff3/diff3prog.c	2020/06/26 07:28:47	1.20
--- src/usr.bin/diff3/diff3prog.c	2021/04/13 14:20:23	1.21
***************
*** 1,4 ****
! /*	$OpenBSD: diff3prog.c,v 1.20 2020/06/26 07:28:47 stsp Exp $	*/
  
  /*
   * Copyright (C) Caldera International Inc.  2001-2002.
--- 1,4 ----
! /*	$OpenBSD: diff3prog.c,v 1.21 2021/04/13 14:20:23 stsp Exp $	*/
  
  /*
   * Copyright (C) Caldera International Inc.  2001-2002.
***************
*** 494,499 ****
--- 494,501 ----
  		do {
  			c = getc(fp[0]);
  			d = getc(fp[1]);
+ 			if (c == -1 && d == -1)
+ 				break;
  			if (c == -1 || d== -1)
  				trouble();
  			nchar++;