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Sd card mount/unmount

Sd card mount/unmount

(1) By ayagmur75 on 2020-06-04 09:17:51 [link]

We have been using a device which has linux operating system. We have been keeping sqlite database file in a sd-card. In normal conditions, after mounting/unmouting we use sqlite database without problem. But sometimes, randomly, we can encounter with an unmount problem: "resource or device busy".

As far as I know, sqlite can cause some problems with network-mounted file systems. I wonder if sd-card mounted file system cause also this kind of error?

Can you please help me?

Thank you very much

(2) By ayagmur75 on 2020-06-04 10:47:18 in reply to 1 [link]

I forgot to add some code. Problem occurs in this sequence;




Best regards,

(3) By anonymous on 2020-06-07 12:51:14 in reply to 2

> `sqlite3_close(db);`

You should check the return value of this call. If the returned value is not `SQLITE_OK`, the database isn't actually closed, and you have leaks of some other resources depending on `db` (e.g. prepared statements). See <https://sqlite.org/c3ref/close.html> for more information on that.

If you do get `SQLITE_OK` from `sqlite3_close`, consider using `lsof` or `fuser` to find out if there are any open filehandles on that filesystem. (On an embedded device, where you cannot use `lsof` or `fuser` because they don't fit in the image, you can iterate over `/proc/*/fd`. But this is an embedded Linux question, not an SQLite question.)