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.
