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Message-Id: <tffytfyohb.ytf@mail.opusnet.com>
Date: Fri, 12 Aug 2005 11:55:12 -0700
From: "Gary W. Swearingen" <garys@opusnet.com>
Reply-To: garys@opusnet.com
To: FreeBSD-gnats-submit@freebsd.org
Subject: [patch] fdisk(8) manpage doesn't warn fdisk doesn't read disk
X-GNATS-Notify:

>Number:         84849
>Category:       docs
>Synopsis:       [patch] fdisk(8) manpage doesn't warn fdisk doesn't read disk
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-doc
>State:          closed
>Quarter:        
>Keywords:       
>Date-Required:  
>Class:          doc-bug
>Submitter-Id:   current-users
>Arrival-Date:   Fri Aug 12 19:00:29 GMT 2005
>Closed-Date:    Fri Oct 13 15:19:53 GMT 2006
>Last-Modified:  Fri Oct 13 15:19:53 GMT 2006
>Originator:     Gary W. Swearingen
>Release:        FreeBSD 5.4-RELEASE i386
>Organization:
none
>Environment:
n/a
>Description:

The fdisk(8) manpage doesn't warn that fdisk doesn't read the disk,
but instead uses "in-core disklabel".

>How-To-Repeat:
n/a

>Fix:
Put a warning in the BUGS section.

--- fdisk..orig.8	Sat Aug  6 15:12:37 2005
+++ fdisk.8	Sat Aug  6 15:35:38 2005
@@ -455,3 +455,11 @@
 The
 .Xr bsdlabel 8
 command must be used for this.
+.Pp
+The program uses the kernel's knowledge of important disk information
+(AKA
+.Qq in-core disklabel ) ,
+so the program can behave unexpectedly if this information is changed
+on the disk without the kernel's knowledge, as is commonly done using,
+for example,
+.Ic "dd if=/dev/zero of=/dev/fd0 count=1" .
>Release-Note:
>Audit-Trail:
State-Changed-From-To: open->closed 
State-Changed-By: ru 
State-Changed-When: Fri Oct 13 15:17:35 UTC 2006 
State-Changed-Why:  
fdisk(8) does read the disk to read the slice table; it only 
doesn't use the disk to determine certain parameters such as 
the number of cylinders, heads, and sectors/track.  These 
parameters don't change if you write to sector 0 of the disk. 

http://www.freebsd.org/cgi/query-pr.cgi?pr=84849 
>Unformatted:
