Monitor (tail -f) prompts to reload file

jhyslop

In version 7.6.6, if I turn on monitoring (View -> Monitor), whenever the file changes NPP is now popping up a message box asking if I want to reload it. Well, yes, of COURSE I want to reload it - that’s why I turned on monitoring!

In the previous version NPP automatically reloaded the file.

Meta Chuh

welcome to the notepad++ community, @jhyslop

i believe you, albeit not being able to reproduce this.
(see screencast below, with working monitoring on 7.6.6 x64)

we had a second report about this, so we suppose it might be a setting, plugin, or leftover from an old installation that could cause this.

please test the following, to verify, if a clean notepad++ (without any plugins or settings that could cause this) would work on your system.

download the notepad++ 7.6.6. 64 bit portable version from >>> here <<<.
(the portable version does not require any installation and runs completely independent and isolated from your installed version. all custom settings, as well as any stuff you might want to try at the portable version, will not modify your installed version)
extract npp.7.6.6.bin.x64.zip to e.g. your desktop.
important note: make sure to close all instances of notepad++ that might be running, before starting the portable version at the next step, to be sure you are using the portable version for this test.
open the extracted npp.7.6.6.bin.x64 folder and start this portable version by double-clicking on notepad++.exe inside this folder.
(note: notepad++.exe will just be seen as notepad++, if you have enabled to hide all known file extensions at your explorer settings)
retry monitoring (tail -f) on the same files using this portable version.

working monitoring (tail -f) on 7.6.6. x64:
Imgur

many thanks and best regards

IT Staff

I have been seeing this same issue. I tried the suggestion of downloading the zip and running in portable mode, but still seeing prompts to reload the file. Sometimes it does update the file even though it prompts, and sometimes I have to acknowledge the prompt to get it to reload. I did occasionally see this behaviour in the past but it was very rare. I noticed that so far I have only been able re-create this issue when monitoring files on the network. When I monitor a file on my local computer I have not yet seen the prompt (although I rarely do this).

Meta Chuh

@IT-Staff

this issue is verified as reproducible.
@SinghRajenM has committed a fix that solves all testing scenarios so far.
the fix is currently in the queue and might get merged, if no further issues or concerns arise.

best regards.

melle sterk

I had the same problem with a 32-bit version(v.7). I installed this solved my problem 64 v.7.6.4

melle sterk

@melle-sterk I cant edit my prev submission. but I do still have the problem after installing both version. it only looked like it dindt for a second. So ignore my prev message

Paul Renold

Still seems to be an issue with v7.7

Meta Chuh

welcome to the notepad++ community, @Paul-Renold

yes, you are correct.

a fix has been submitted to address this issue, but it has not been merged into 7.7 for issue strategic reasons, due to the major changes within this release.

many thanks and best regards.

Manuel Romeiro

I installed the V7.8 32-bit (built time Oct 7 2019 - 00:58:16) and continue not working.
Now, there is not prompt, but don’t update the changes.

Manuel Romeiro

Improving my last answer.
The functionality “tail -f” seams working when data changes and stream is closed, but sometimes not works if the file stream remains opened.

I tested it, redirecting java application output to one file (some_java_application > out.log).
The Notepad++ only updated at the begin (when file was cleaned) and at the end (when application ends, and file stream was closed).
If I disable the “tail -f”, the prompt comes again as expected, when focus in Notepad++ with files changes, even when stream remains opened (that means the Notepad++ have capability to detect changes on files with stream open, but not when “tail -f” enabled).
I’ll comment again if I reproduce this with a simple application, but bellow I reproduce partially with native ms-dos applications.

After that, I tried to reproduce the problem only using windows base applications, and that works better, but not perfect.
Executing the bellow command on the console:
ping -t 0.0.0.0 > test_tail_notepad_plus_plus.txt

The Notepad++ with “tail -f” enablled only updates when:

At the begin, when file was cleared;
Receiving focus on Notepad++;
Press F5 on Explorer with file folder opened (native file Explorer of windows);

There are missing updates on acceptable time for tail functionality, even Notepad++ don’t have focus (for example refresh rates of 1 second).
I’m running Notepad++ V7.8 32bit on windows 10 64bit.

Thanks
Manuel Romeiro

SinghRajenM

@Manuel-Romeiro it seems these all are windows limitation. It is explained here - https://github.com/notepad-plus-plus/notepad-plus-plus/pull/5591#issuecomment-487341747

Refreshing every second could be an option. But it will keep utilizing CPU even if there is no change as well because the monitoring thread has to do polling every second which is against the design of change notification.

SinghRajenM

For reference to all -

From MSDN

FILE_NOTIFY_CHANGE_SIZE
0x00000008

Any file-size change in the watched directory or subtree causes a change notification wait operation to return. The operating system detects a change in file size only when the file is written to the disk. For operating systems that use extensive caching, detection occurs only when the cache is sufficiently flushed.

FILE_NOTIFY_CHANGE_LAST_WRITE
0x00000010

Any change to the last write-time of files in the watched directory or subtree causes a change notification wait operation to return. The operating system detects a change to the last write-time only when the file is written to the disk. For operating systems that use extensive caching, detection occurs only when the cache is sufficiently flushed.

Manuel Romeiro

@SinghRajenM Yes, it’s exactly that issue.
I’ll continue using the functionality knowing that limitation.
Thanks

ryangray01

@Manuel-Romeiro said in Monitor (tail -f) prompts to reload file:

Improving my last answer.
The functionality “tail -f” seams working when data changes and stream is closed, but sometimes not works if the file stream remains opened.

I tested it, redirecting java application output to one file (some_java_application > out.log).
The Notepad++ only updated at the begin (when file was cleaned) and at the end (when application ends, and file stream was closed).
If I disable the “tail -f”, the prompt comes again as expected, when focus in Notepad++ with files changes, even when stream remains opened (that means the Notepad++ have capability to detect changes on files with stream open, but not when “tail -f” enabled).
I’ll comment again if I reproduce this with a simple application, but bellow I reproduce partially with native ms-dos applications.

After that, I tried to reproduce the problem only using windows base applications, and that works better, but not perfect.
Executing the bellow command on the console:
ping -t 0.0.0.0 > test_tail_notepad_plus_plus.txt

The Notepad++ with “tail -f” enablled only updates when:

At the begin, when file was cleared;
Receiving focus on Notepad++;
Press F5 on Explorer with file folder opened (native file Explorer of windows);
There are missing updates on acceptable time for tail functionality, even Notepad++ don’t have focus (for example refresh rates of 1 second).
I’m running Notepad++ V7.8 32bit on windows 10 64bit.

Thanks
Manuel Romeiro

The “tail -f” functionality in Notepad++ works as expected when the file stream is closed, but encounters issues when the file stream remains open. I tested this by redirecting the output of a Java application to a file (some_java_application > out.log), and Notepad++ only updated at the beginning (when the file was cleared) and at the end (when the application finished and the stream was closed). However, when the stream remained open, the updates were not consistent. I further tested this with a native Windows command (ping -t 0.0.0.0 > test_tail_notepad_plus_plus.txt), and the updates only occurred when the file was cleared, when Notepad++ regained focus, or when the folder view was refreshed using F5 in Windows Explorer. Updates were missed when the file was actively being written to and Notepad++ didn’t have focus, indicating that Notepad++ can detect file changes while the stream is open, but not reliably with “tail -f” enabled. This behavior is similar to discovering in n out secret menu prices—unexpected yet interesting, but inconsistent. This was tested on Notepad++ v7.8 (32-bit) on Windows 10 (64-bit).