ntfs-3g milliseconds lost

qrange · 08-27-2018, 01:49 PM

When I unpack .rar file onto ntfs(3g) mounted partition, it seems that milliseconds in 'Modify' timestamp are simply lost (cut off).
Is there a way to keep them?

thanks.

rtmistler · 08-27-2018, 02:38 PM

So you're saying that you unpack them onto a type 83 file system and the timestamp retains milliseconds?

If so, unpack them on a Linux partition, and then copy them to the NTFS partition and see what happens. My suspicion is that the NTFS partition will not timestamp files using that level of precision.

michaelk · 08-27-2018, 04:35 PM

If I understand timestamps, your question and what you are actually referring to then the answer is no. Otherwise you need to provide some additional information.

Your correct NTFS does not. I don't know how ntfs-3g handles timestamps. linux uses nanosecond time stamps but NTFS is only 100 nanosecond time stamp. To illustrate I created a text file on a ext4 filesystem and copied it to an external NTFS USB drive preserving time stamps. The fractional part of time was .274039542 versus 274039500.

Quote:

touch test.txt
stat ctime.txt

Access: 2018-08-27 15:43:29.274039542
Modify: 2018-08-27 15:43:29.274039542
Change: 2018-08-27 15:43:29.274039542

cp -p ctime.txt /media/goflex1/

stat test.txt

Access: 2018-08-27 15:43:29.274039500
Modify: 2018-08-27 15:43:29.274039500
Change: 2018-08-27 15:43:51.538605000

If you create a file on a NTFS filesystem it seems like the atime and mtime are to the nearest second but ctime is to the nearest 10 microseconds.

Quote:

/media/goflex1# touch text1.txt
/media/goflex1# stat text1.txt

Access: 2018-08-27 15:44:59.000000000
Modify: 2018-08-27 15:44:59.000000000
Change: 2018-08-27 15:44:59.529160000

https://docs.microsoft.com/en-us/win...nfo/file-times

qrange · 08-28-2018, 01:34 AM

sorry, I was wrong. forget ntfs3g part.

I need to unpack a .rar file (that was created on Windows) onto ext4 partition and retain exact same timestamp, so that later I can re-pack it to identical .rar file (probably by using same rar version in wine).

jefro · 08-28-2018, 12:58 PM

"KeepFileStamp=0" then??

michaelk · 08-28-2018, 03:53 PM

I forgot to ask what you meant about 'Modify' timestamp are simply lost (cut off).

jefro that got me thinking.

I am not familiar enough with winRAR but depending on version there appears to be an option to select high precision time format (100 ns time) when archiving files. If this is not set then I would assume the modification time to have less precision which is what I assumed you meant by cut off.

I would expect unpacking a file would maintain the same modification time with the same precision as the original file. If the file is unmodified then I would assume using the same version with the same options under wine to keep the same precision.

qrange · 08-31-2018, 03:30 PM

@jefro

"KeepFileStamp=0" (or 1) doesn't work for some reason.
I'm using ext4 with these options: /dev/sda1 on / type ext4 (rw,relatime,discard,commit=60,data=ordered)

Code:

1000@debian:~/vdi/vbox_shr/rartest$ rar lt rar500.rar 

RAR 5.40   Copyright (c) 1993-2016 Alexander Roshal   15 Aug 2016
Trial version             Type RAR -? for help

Archive: rar500.rar
Details: RAR 4

        Name: Rar500.exe
        Type: File
        Size: 488024
 Packed size: 230168
       Ratio: 47%
       mtime: 2013-08-22 19:01:18,235
  Attributes: ..A....
       CRC32: 98FD70D0
     Host OS: Windows
 Compression: RAR 3.0(v29) -m3 -md=512K

1000@debian:~/vdi/vbox_shr/rartest$ unrar x -KeepFileStamp=0  rar500.rar 

UNRAR 5.30 beta 2 freeware      Copyright (c) 1993-2015 Alexander Roshal


Extracting from rar500.rar

Extracting  Rar500.exe                                                OK 
All OK
1000@debian:~/vdi/vbox_shr/rartest$ ls -lan --time-style=full-iso
total 716
drwxr-xr-x  2 1000 1000   4096 2018-08-31 22:23:50.593784620 +0200 .
drwxr-xr-x 11 1000 1000   4096 2018-08-31 22:20:28.658761091 +0200 ..
-rw-r--r--  1 1000 1000 488024 2013-08-22 19:01:18.000000000 +0200 Rar500.exe
-rw-r--r--  1 1000 1000 230242 2018-08-31 22:20:55.882625587 +0200 rar500.rar