Re: Bug in the file attributes ?

[Brian Beattie]

On Thu, 29 Mar 2001, Andreas Dilger wrote:

> Xavier Ordoquy writes:
> > I just made a manipulation that disturbs me. So I'm asking whether it's a
> > bug or a features.
> > 
> > user> su
> > root> echo "test" > test
> > root> ls -l
> > -rw-r--r--   1 root     root            5 Mar 29 19:14 test
> > root> exit
> > user> rm test
> > rm: remove write-protected file `test'? y
> > user> ls test
> > ls: test: No such file or directory
> > 
> > This is in the user home directory.
> > Since the file is read only for the user, it should not be able to remove
> > it. Moreover, the user can't write to test.
> 
> This is definitely not a bug.  Deleting a file (under *nix) does not
> "modify" the file at all, it is modifying the directory where the file
> resides.

To be correct and pedantic, in a traditional Unix type filesystem, one
does not remove a file...one dereferences it, i.e. "unlink", as part of
this process garbage collection is performed which checks the reference
count. If the inode's reference count is zero, the inode and data blocks
are returned to their respective free lists.  All the rm command does, is
to remove the directory entry and decrement the reference count :).  This
is why Unix has a rm (remove link) as opposed to a del (delete file)
command.

Brian...just being pedantic :-^

Brian Beattie
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