On Sat, 10 Mar 2018, Stephen Morris wrote:
On 9/3/18 9:11 am, Patrick O'Callaghan wrote:
> On Fri, 2018-03-09 at 07:59 +1100, Stephen Morris wrote:
>> It is my understanding that currently when a file copied to any
>> location, a physical copy is not produced, the copy is a hardlink
>> to the original file, until such time as one of the "copies" is
>> changed and then both become physical files with one file
>> reflecting the pre-change contents
> What you describe here is linking, not copying. Copying always
> produces an apparently independent file ('Apparently' because on
> Copy-On-Write filesystems they two may actually share disk blocks
> until one of them changes, but that is *not* the same as linking).
No, what I was mentioning here is what I have read as standard linux
functionality with copying, when a file is copied, and it doesn't
matter where to, rather than create a 2nd copy of the file, the
"copy" is created as a hard link to the original file, for storage
efficiency, and then when one of the files is updated the hardlink
is broken and both files become physical.
AFAIK, "copying" in unix/linux has never worked that way; if you can
provide a link that describes it that way, that would be interesting.
rday