Locked File bug

[genoasalami]

As always, thanks to Kovid the dev for all the hard work put into Calibre!

This is sort of a long-standing bug, but I was hoping it could be corrected; I think it's an easy fix.

I keep my Calibre library and all books on a network folder so that it can be accessed by any computer with Calibre on the network.* Frequently, when I am editing metadata, I get the following error message:

Locked file: J:\Documents\Books\author\book\book.epub

Traceback (most recent call last):
  File "site-packages\calibre\gui2\metadata\single.py", line 579, in apply_changes
  File "site-packages\calibre\gui2\metadata\basic_widgets.py", line 220, in commit
  File "site-packages\calibre\db\legacy.py", line 824, in func
  File "site-packages\calibre\db\cache.py", line 62, in call_func_with_lock
  File "site-packages\calibre\db\cache.py", line 1095, in set_field
  File "site-packages\calibre\db\cache.py", line 1109, in update_path
  File "site-packages\calibre\db\backend.py", line 1568, in update_path
  File "site-packages\calibre\db\backend.py", line 1445, in copy_format_to
  File "site-packages\calibre\utils\filenames.py", line 429, in copy_path_to
  File "site-packages\calibre\startup.py", line 116, in local_open
IOError: [Errno 13] Permission denied: u'J:\\Documents\\Books\\author\\book\\book.epub'

After a minute or so, if I try again (i.e., click OK or next in the metadata editor), it'll process just fine. Presumably something Calibre is doing is locking the file and preventing changes, but-whatever that is-it stops after a minute. It's not unusable, but it does slow things down.



* This error appears even if no other network device is accessing the library. In other words, everything else can be completely powered down, but the files are still locked, so I am pretty sure it's Calibre doing the locking/unlocking

[theducks]

Calibre IS NOT network share or NAS friendly (it is in the FAQ)

NAS should only be used to shadow your current library and should NOT sync while Calibre is in use. Bad things (race conditions...) can happen

[genoasalami]

Originally Posted by theducks

Calibre IS NOT network share or NAS friendly (it is in the FAQ)

I've had this setup for quite a while and this is the only minor problem I've ever had. So I'd actually say it works pretty well.

NAS should only be used to shadow your current library and should NOT sync while Calibre is in use. Bad things (race conditions...) can happen

Not sure what you mean by syncing; that's not how NAS works. As far as OSX/Windows/Calibre are concerned, it's a local drive.

I'm not actually even totally convinced this error is solely related to the fact the drive is networked.

[DoctorOhh]

Originally Posted by genoasalami

I've had this setup for quite a while and this is the only minor problem I've ever had. So I'd actually say it works pretty well.

You've been fortunate. Calibre does not officially support running from a NAS.

https://manual.calibre-ebook.com/faq...rked-drive-nas

Originally Posted by genoasalami

I'm not actually even totally convinced this error is solely related to the fact the drive is networked.

You'll get that error anytime another program is accessing calibre or its files / folders when you attempt to change title or author information. When I don't pause syncing on Dropbox I often get the same error.

[solomon]

Calibre 2.xx worked quite well this way - I have a similar setup where one system runs calibre-server and stores the library & database, then another client accesses the library/database over the network.

With the Calibre 3.x content server looking like it will be writing to the database not just reading it, Kovid seems like he's really precluding this type of usage model. I get that's probably Ok for most users, but like the OP, I wish for a few seemingly small concessions which would permit this.