Re: Identifying sparse files using getattrlist()
Re: Identifying sparse files using getattrlist()
- Subject: Re: Identifying sparse files using getattrlist()
- From: rohan a <email@hidden>
- Date: Tue, 3 Nov 2009 16:34:31 +0530
When I use
# mkfile -nv 4g sparse
on a 7GB Apple_UFS partition
df -k gives me this :
#df -k
Filesystem 1024-blocks Used Available Capacity Mounted on
/dev/disk2s3 7390568 40 7021000 1% /Volumes/UFSVolume
This indicates that the file created is sparse since it shows Capacity as 1%
On Tue, Nov 3, 2009 at 4:27 PM, Alastair Houghton
<email@hidden> wrote:
> On 2 Nov 2009, at 13:37, rohan a wrote:
>
>> I am trying to identify if a particular file is a sparse file using
>> getattrlist()
>>
>> I am using this : attrList.fileattr = ATTR_FILE_TOTALSIZE |
>> ATTR_FILE_ALLOCSIZE;
>>
>> According to the man page if ATTR_FILE_ALLOCSIZE <
>> ATTR_FILE_TOTALSIZE the file is a sparse file.
>>
>> I created the sparse file using dd
>> #dd if=/dev/zero of=sparse-file bs=1 count=0 seek=3g
>>
>> However, both AllocSize and TotalSize are returning the same size
>> while actually AllocSize < TotalSize
>>
>> I am using UFS
>
> Does Apple UFS even support sparse files? Remember, UFS is a name used by a
> fair number of totally different and usually incompatible filesystems. I
> haven't really ever bothered investigating exactly what Apple's UFS can and
> can't do... indeed, I've always had the impression that it was only really
> present for the benefit of old-time NeXT users who might have compatible
> filesystems floating around already.
>
> Kind regards,
>
> Alastair.
>
> --
> http://alastairs-place.net
>
>
>
>
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Darwin-dev mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden