diff -cr unroff-1.0.orig/src/error.c unroff-1.0/src/error.c
*** unroff-1.0.orig/src/error.c	Fri Jun  2 15:16:00 1995
--- unroff-1.0/src/error.c	Mon Feb 12 18:53:17 1996
***************
*** 39,45 ****
--- 39,47 ----
  
  static char *strerr(void) {
      extern int sys_nerr;
+ #ifndef BSD
      extern char *sys_errlist[];
+ #endif
  
      return errno > 0 && errno < sys_nerr ?
  	sys_errlist[errno] : "unknown error";