Detect size only change #95
Open
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
ScanNow() causes the file watch loop to run once, and ensures all events have been posted before returning. It allows the caller to "synchronize" with the pending watcher events, so is useful for batch updating after it is known file events have probably occurred.
On some file systems, multiple changes to the same file within the file system's mod time resolution would be missed. This issue can be ameliorated by triggering `Write` events if a size change is detected, even if no corresponding mod time change occurs. Changes to the file content without a change to the size or mod time will still go unnoticed.
dideler
added a commit
to dideler/watcher
that referenced
this pull request
Apr 21, 2020
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
This PR builds on #94
Sometimes the watcher would not detect file changes if successive changes to a file happened very quickly, specifically within the min resolution that the underlying file system could represent for mod time stamps. In my case, I was testing on a file system which had 1 second mod time stamp resolution. If I edited a file twice in 1 second, then the second write event was lost.
This was principally visible in some unit tests where a series of quick modifications to files happened to occur, but it could happen in real situations also I guess, hence this fix.
The fix simply emits a
Writeevent if the mod time changes OR if the size changes.