Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 4 Aug 1998 22:13:22 +0200 (CEST)
From:      Sascha Schumann <sas@schell.de>
To:        moi <poipoi@famipow.com>
Cc:        freebsd-fs@FreeBSD.ORG, linux-fsdevel@vger.rutgers.edu
Subject:   Re: file hole ?
Message-ID:  <Pine.BSF.4.01.9808042203230.13693-100000@guerilla.foo.bar>
In-Reply-To: <19980804175705.377.qmail@hwi.poi.org>

next in thread | previous in thread | raw e-mail | index | archive | help

man 2 lseek:

"The lseek() function allows the file offset to be set beyond the end of
the existing end-of-file of the file. If data is later written at this
point, subsequent reads of the data in the gap return bytes of zeros
(until data is actually written into the gap). ..."

Most fs' I know (including UFS and ext2fs) preallocate blocks before data
is written, so you will never have this kind of file fragmentation. 

HTH,
       Sascha

On Tue, 4 Aug 1998 poipoi@famipow.com wrote:

> 	hi
> 
> 	i want to know how to handle file hole. 
> for example, i have a 8k file. i do a seek at 20000 and write a byte. 
> 
> Does the fs alloc every block to store 20001 bytes ?
> yes ? but its a space wasting...
> no ? but when the user will fill the hole (writing from 8192 to 20000),
> my fs will perhaps be full and i have to reject the write operation...
> 
> what is the standard (good?) behaviour ? and why (if possible) ?
> 
> To Unsubscribe: send mail to majordomo@FreeBSD.org
> with "unsubscribe freebsd-fs" in the body of the message
> 


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-fs" in the body of the message



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.BSF.4.01.9808042203230.13693-100000>