Rare Null Write Glitch

Samuel Cool

I was just working on a css file, and I think I hit ctrl+shift+s for a save all, and suddenly the file blanked out, and I quickly found out that it had cleared everything somehow, then saved, or something like that. But the end result: I lost the entire file, no getting it back. I have a backup, but it’s pretty old, I might as well rewrite it all.

If anyone can find the bug that caused this, and save others from the same fate, I’d be grateful.

-Samuel

chcg

Unfortunately this is seems to be a not to seldom problem, see e.g.
https://notepad-plus-plus.org/community/topic/14512/crash-then-current-file-empty
https://notepad-plus-plus.org/community/topic/14623/np-7-5-1-version-crashed-and-data-lost
https://notepad-plus-plus.org/community/topic/14463/i-have-lost-my-html-file-data-after-notepad-crashed-while-i-am-unable-to-find-the-any-backup-file-of-that-date-of-my-file-in-notepad-backup-directory
https://notepad-plus-plus.org/community/topic/14313/how-can-i-restore-my-old-backup-files
https://notepad-plus-plus.org/community/topic/14294/notepad-crashed-i-lost-all-data-in-a-file

, but typically that happens in relation with a N++ or OS crash.

Claudia Frank

@chcg

I guess this needs to be divided into, at least, two different issues.
One which causes the file to be erased and the other resulting in a NULL-filled file.

If the file is completely empty this could lead to the assumption that the file
was opened and before flushing the content the write operation was interrupted.
Either by os shutdown, process dying etc…
This kind of issue cannot be prevented in a 100% guaranteed way.

The other issue where a file is filled with NULLs is a little bit strange as it is not clear
why this happens at all. I’m suspecting backup functionality but because I haven’t found a
way to prove this it still could mean I’m wrong.

Recently I started investigating what could be done to find out under which circumstance
a file will be filled with NULLs but, unfortunately, haven’t yet found a secure way for monitoring
this.

Cheers
Claudia

Alan Kilborn

@Samuel-Cool said:

rare null write

suddenly the file blanked out,

cleared everything somehow

What is “null write”, “blanked out”, “cleared everything”? Such a serious thing deserves a better bug report if it is to get addressed.

And a backup that is “pretty old” is no backup at all. That’s on you, not Notepad++.

Sorry to be brutal…facts are facts.

Samuel Cool

@Claudia-Frank To be clear, the file became 0kb. It literally has nothing int it.

Samuel Cool

@Alan-Kilborn I realize having only an old backup is my fault. I assure you, I won’t be making that mistake twice.

Samuel Cool

The current file blanked out while I was looking at it when I tried to save all, so it’s definitely notepad++'s fault.

Claudia Frank

@Samuel-Cool

may I ask, you used save all to save all open files or just save to save the current file or
you used save all but only one file was opened at that time?

If you used save all for all open files, were additional files affected or only this one?
Btw. do you use npp’s backup functionality and if so, what is the configuration?

Cheers
Claudia

Samuel Cool

@Claudia-Frank I had two files opened, css file was the one deleted, and an html file on the tab to the right, which was unaffected.

I use the plugins Autosave and Autosave 2, but only after this happened, no other backup functionality is set up.

Claudia Frank

@Samuel-Cool

… and you used save all or just save in this case?
Was there anything to save for the html file or was it not modified at that time.

Btw. could you post the debug-info? (available under ? menu)

Cheers
Claudia

Scott Sumner

@Samuel-Cool said:

I use the plugins Autosave and Autosave 2

Maybe it is Autosave’s fault…somehow…?
Saving right at the instant the user does…maybe an interaction?
Hmmm…
Just a thought…

Samuel Cool

@Claudia-Frank Notepad++ v7.5.3 (32-bit)
Build time : Dec 5 2017 - 10:45:46
Path : C:\Program Files\Notepad++\notepad++.exe
Admin mode : OFF
Local Conf mode : OFF
OS : Windows 7 (32-bit)
Plugins : AutoSave.dll autosave2.dll DSpellCheck.dll mimeTools.dll NppConverter.dll NppExport.dll NppFTP.dll PluginManager.dll

I used save all, the html file likely hadn’t been modified recently.

By the way, this happened before updating, I think I was in 7.4. I think it’s worth noting that the 7.4.1 release log says “The opened zero length file not saving bug.” was found, possibly related.

Samuel Cool

@Scott-Sumner I didn’t have those plugins installed at the time.

Claudia Frank

@Samuel-Cool

Just to summarize what happened

Npp most likely version 7.4
Using no npp backup functionality and no plugins which do backup files at that time.
When pressing save all the entire current active file got erased, other files weren’t
affected although it might be that other files haven’t had any modification at that time.
Npp kept running - no crash or npp restart.

Correct?

Cheers
Claudia

Samuel Cool

@Claudia-Frank Correct.

kingtls

@Claudia, just to confirm I encountered the same just two days ago. I still have NPP open as I am still trying to find a way to see if there is any chance to recover my files (2x).

I believe there are TWO issues here:

npp sudden nulling / blanking of file(s) when there is nothing going on (was in the meeting, not using laptop at the time)
backup mechanism not working

here is my debug-info:

Notepad++ v7.5.1 (64-bit)
Build time : Aug 29 2017 - 02:38:44
Path : C:\Program Files\Notepad++\notepad++.exe
Admin mode : OFF
Local Conf mode : OFF
OS : Windows 7 (64-bit)
Plugins : mimeTools.dll NppConverter.dll

I had posted details info here:
https://notepad-plus-plus.org/community/topic/15112/attempt-to-recover-files-after-npp-blank-2-files-after-error-missed-the-error-msg

ps: @Allan, it is not a user’s fault

Gogo Neatza

It seems to me that more people with “Local Conf mode : OFF”
are having this kind of trouble than the others.

Claudia Frank

@Gogo-Neatza

I assume this is because it is the default setting.
But who knows.

@kingtls

So it seems there are three types of a similar issue.

left file completely blank
left file fill with null char
but both happened with a crash of npp beforehand and
left a file with blanks but npp kept running.

Cheers
Claudia

chcg

See https://github.com/notepad-plus-plus/notepad-plus-plus/issues/2883#issuecomment-360502864 might be interesting:

After a Notepad++ crash with nullified file(mostly after save the file), you can try to restart notepad++! by executing the .exe directly. It comes up with a message that ‘another program changed your nullified file’ and it will ask to reload the file. DON’t reload (it is nullified in the original map) but after give your answer (DON’t reload) Notepad++ comes up with the nullified file: magical is not? Somewhere in memory it is keep alive!!
Hopefully this saved other people some headaches!! It was for me.