Save sketch recreate the sketch file and break the hard link

[45gfg9]

OS: macOS 10.14.6
IDE: 1.8.10
We create a hard link to a sketch:

$ ln ~/Documents/Arduino/test/test.ino ~
$ ls -li ~/Documents/Arduino/test/test.ino ~/test.ino
12898678091 -rw-r--r--  2 45gfg9  staff  225  2 14 13:21 /Users/45gfg9/Documents/Arduino/test/test.ino
12898678091 -rw-r--r--  2 45gfg9  staff  225  2 14 13:21 /Users/45gfg9/test.ino

Go to IDE and change the sketch, then

$ ls -li ~/Documents/Arduino/test/test.ino ~/test.ino
12898678261 -rw-r--r--  1 45gfg9  staff  221  2 14 13:23 /Users/45gfg9/Documents/Arduino/test/test.ino
12898678091 -rw-r--r--  1 45gfg9  staff  225  2 14 13:21 /Users/45gfg9/test.ino

[matthijskooijman]

Are you sure this issue is fixed? I can see that the code would fix symlinks, but this issue is about hardlinks (which is tricky to fix with the current write-then-rename approach, I think to work with hardlinks you'll have to write directly to the original file, with the risk of half-overwriting it on errors such as disk full).

[45gfg9]

Same... I can't sure whether it's fixED or not cuz both the build && the branch was deleted. You said it's about symlinks but not hard links :( I'll build one myself later.

[per1234]

@45gfg9 the test builds were deleted for #8744 because #8744 has been merged into the master branch, and thus is now available for testing in the hourly build of the Arduino IDE:
https://www.arduino.cc/en/Main/Software#hourly

[cmaglie]

I can see that the code would fix symlinks, but this issue is about hardlinks

I see, I don't think it's fixed.

[Humancell]

I'm curious what Release or version this might be fixed in? I'd like to test it. I've tried using symlinks and hardlinks on Windows (using mklink) and in both cases when I save a sketch file it is deleting the link and then creating a new file in it's place.

I'm guessing the fix being worked on would follow the link and save over the original file?

BTW ... this would be a REALLY great feature I've been looking for!

[MartyMacGyver]

Same issue on Windows 10 - soft and hard symlinks work great right up until you save - then Arduino decides to completely replace the link with a new file. There's no useful reason for this behavior - Arduino can plainly read from a symlink, and writing should be no stretch - and it makes library development unnecessarily difficult.

[MartyMacGyver]

This is the part that makes zero sense to me... normally if you're saving a file and it exists, you open it, write to it, close it, and you're done.

Instead, the IDE does a strange dance of deleting the file first, then replacing it with what was a temp file.

Arduino/arduino-core/src/processing/app/BaseNoGui.java

Line 903 in fb9ce0a

boolean result = file.delete();

How about, instead of locating the original file and destroying it and therefore breaking its symlinks, the IDE simply updates the file in place in a normal way?

[MartyMacGyver]

And this appears to be the second attempt to fix the same problem:

#5478

The original problem appears to have started about 10 years ago as part of a sync from Processing.

2e26a2d#diff-b6fda0bf6be0a53c0741a9b02ac16f37R1902

The problem persists in Processing to this day:

https://github.com/processing/processing/blob/b9049243bd74c8a6395f102944f04ca5196ec43d/app/src/processing/app/Util.java#L193

Is there any will to actually fix the underlying problem in a way that necessarily fixes Processing's broken precedent in this regard?