diff -u -r ../bvi-1.4.0/comm.c ./comm.c
--- ../bvi-1.4.0/comm.c	2014-01-29 14:54:53.000000000 +0000
+++ ./comm.c	2017-07-07 07:11:55.310380582 +0000
@@ -84,10 +84,10 @@
 extern	char	*name;			/* actual filename */
 extern	char	**files;		/* used for "next" and "rewind" */
 extern	int		numfiles, curfile;
-extern	int		errno;
 
 static	char	oldbuf[CMDSZ];		/** for :!! command **/
 
+int save_chk(char* fname, char* start, char* end, int flags);
 
 /*
  * docmdline() - handle a colon command