Enable dirty buffer detection in mg.

Emulate the emacs behavior: after suspend/resume, buffer switch,
or at save time, warn (prompt) the user if the file has been modified
on disk in the interim.
This has already saved my butt numerous times.
ok phessler

1 files changed, 7 insertions, 2 deletions

diff --git a/usr.bin/mg/def.h b/usr.bin/mg/def.h
index f26d46a2505..542a07c084e 100644
--- a/usr.bin/mg/def.h
+++ b/usr.bin/mg/def.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: def.h,v 1.106 2008/06/14 08:39:30 kjell Exp $	*/
+/*	$OpenBSD: def.h,v 1.107 2008/09/15 16:11:35 kjell Exp $	*/
 
 /* This file is in the public domain. */
 
@@ -272,7 +272,8 @@ struct buffer {
 #endif
 #define BFOVERWRITE 0x08		/* overwrite mode		 */
 #define BFREADONLY  0x10		/* read only mode		 */
-
+#define BFDIRTY     0x20		/* Buffer was modified elsewhere */
+#define BFIGNDIRTY  0x40		/* Ignore modifications */
 /*
  * This structure holds information about recent actions for the Undo command.
  */
@@ -404,6 +405,7 @@ int		 usebuffer(int, int);
 int		 notmodified(int, int);
 int		 popbuftop(struct buffer *);
 int		 getbufcwd(char *, size_t);
+int		 checkdirty(struct buffer *);
 
 /* display.c */
 int		vtresize(int, int, int);
@@ -424,6 +426,7 @@ void		 free_file_list(struct list *);
 
 /* fileio.c */
 int		 ffropen(const char *, struct buffer *);
+void		 ffstat(struct buffer *);
 int		 ffwopen(const char *, struct buffer *);
 int		 ffclose(struct buffer *);
 int		 ffputbuf(struct buffer *);
@@ -434,6 +437,8 @@ char		*startupfile(char *);
 int		 copy(char *, char *);
 struct list	*make_file_list(char *);
 int		 fisdir(const char *);
+int		 fchecktime(struct buffer *);
+int		 fupdstat(struct buffer *);
 
 /* kbd.c X */
 int		 do_meta(int, int);