Re: rm && opensolaris && ntfs-3g problem

[Jim Meyering]

"Andras Barna" <address@hidden> wrote:
>>> @osol /ntfs: /usr/gnu/bin/mkdir -p t/t/t/t/t/t/t/t/t/t//t/t///t//t/t/t/
>>> @osol /ntfs: /data/a/bin/rm --version|head -1
>>> rm (GNU coreutils) 6.12
>>> @osol /ntfs: /data/a/bin/rm -rf t
>>> @osol /ntfs: echo $?
>>> 0
>>> @osol /ntfs: ls t
>>> t
>>> @osol /ntfs: /data/a/bin/rm -r t
>>> @osol /ntfs: ls t
>>> t
>>> @osol /ntfs: /data/a/bin/rm -r t
>>> @osol /ntfs: echo $?
>>> 0
>>> @osol /ntfs: ls t
>>> t

Thanks for the truss output.
For reference, this seems to be rm -r output (coreutils-6.12):
[note that this appears to be using "l/l/l...", while the commands
above used "t/t/t/..." ]

  fstatat64(AT_FDCWD, "l", 0x080478E0, 0x00001000) = 0
  getprivimplinfo(0x08046FA0, 2076)             = 0
  mmap(0x00010000, 65536, PROT_READ|PROT_WRITE|PROT_EXEC, 
MAP_PRIVATE|MAP_ANON|MAP_ALIGN, -1, 0) = 0xD0780000
  sysconfig(_CONFIG_NGROUPS)                    = 16
  zone_lookup(0x00000000)                               = 0
  zone_getattr(0, ZONE_ATTR_PRIVSET, 0xD0A20248, 12) = 12
  getppriv(PRIV_EFFECTIVE, {00020000e200000000000000}) = 0
  brk(0x080980E0)                                       = 0
  brk(0x0809A0E0)                                       = 0
  access("l", W_OK|E_OK)                                = 0
  getppriv(PRIV_EFFECTIVE, {00020000e200000000000000}) = 0
  unlinkat(AT_FDCWD, "l", 0x00000000)           = 0
  llseek(0, 0, SEEK_CUR)                                = 326816
  close(0)                                      = 0
  close(1)                                      = 0
  close(2)                                      = 0
  _exit(0)

That suggests that the opensolaris ntfs support for unlinkat
doesn't work as documented.  That unlinkat call is succeeding,
yet I presume there is a non-empty directory named "l" that it
fails to remove.

There are two differences in how unlinkat is used between
coreutils and /usr/bin/rm:
  - coreutils uses "0" as the third argument, and /bin/rm uses 0x1
    (which is probably AT_REMOVEDIR)
  - coreutils uses AT_FDCWD as the first argument, and /bin/rm
    uses a file descriptor.

Since Solaris is where openat-style functions originated, I'm
surprised that their ntfs implementation would not adhere to the
documented specification.

I do not plan to make GNU rm work around this bug.