On Tue, Dec 04, 2001 at 10:04:57PM +1100, Mark Hannon wrote:
> Hi Chris,
> 
> This is exactly what I was seeing!  (I finally twigged when I did a 
> low level backup of a filesystem and then noticed that my level 9 
> backup was the same length as the night before ....)
> 
> Thanks, Mark
> 
> 
> "Crist J . Clark" wrote:
> > 
> > I did some more checking on how dump(8) works. If you dump to an
> > existing file, the file can never get smaller. That is, the file is
> > not truncated. I'll look at whether there is a good reason for this.
> > Is this actually what you were describing?

I don't really see a reason why dump(8) needs to work that way. Here
is an untested patch that should change that behavior.

Index: src/sbin/dump/tape.c
===================================================================
RCS file: /export/ncvs/src/sbin/dump/tape.c,v
retrieving revision 1.12.2.1
diff -u -r1.12.2.1 tape.c
--- src/sbin/dump/tape.c        1 Aug 2001 06:29:35 -0000       1.12.2.1
+++ src/sbin/dump/tape.c        4 Dec 2001 11:24:12 -0000
@@ -609,10 +609,10 @@
                }
 #ifdef RDUMP
                while ((tapefd = (host ? rmtopen(tape, 2) :
-                       pipeout ? 1 : open(tape, O_WRONLY|O_CREAT, 0666))) < 0)
+                       pipeout ? 1 : open(tape, O_WRONLY | O_CREAT | O_TRUNC, 0666))) 
+< 0)
 #else
                while ((tapefd = (pipeout ? 1 :
-                                 open(tape, O_WRONLY|O_CREAT, 0666))) < 0)
+                                 open(tape, O_WRONLY | O_CREAT| O_TRUNC, 0666))) < 0)
 #endif
                    {
                        msg("Cannot open output \"%s\".\n", tape);

Is there any reason we don't want to truncate the file? Does O_TRUNC
not work well of the file is a tape device or something?
-- 
Crist J. Clark                     |     [EMAIL PROTECTED]
                                   |     [EMAIL PROTECTED]
http://people.freebsd.org/~cjc/    |     [EMAIL PROTECTED]

To Unsubscribe: send mail to [EMAIL PROTECTED]
with "unsubscribe freebsd-hackers" in the body of the message

Reply via email to