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snarkophilus · 04-02-2012, 11:04 PM

I've also seen an error (sorry, I don't recall the exact wording but I think it might be "invalid page") on my T1 when I try to re-open a book after I modify it (in say Sigil). I've tracked this down to the entry for the book in the "current_position" table in books.db on the device pointing to an invalid location. The actual location in the book is stored as a reference like "OEBPS/Text/asimov-youthebook-3.html#point(/1/4/104/1:252)" and if that position no longer valid you get the error with no way to recover on the reader itself.

There's two ways around this. First, as carpetmojo said, just delete the book from the reader and reload. The second is to use one of the SQLite tools and find your book's ID in the "books" table in the books.db, then delete the entry for that ID that from the "current_position" (remembering that the book ID column is called "content_id" in the "current_position" table). Needless to say I usually use the first option

.

I think, but am not sure, that my old PRS-350 simply went back to the start of the book if it got confused by where it thought your current position was rather than this annoying behaviour on the T1.

I've been thinking of raising a feature request in Calibre to handle this, but I'm still not sure what the right thing to do is. The sledgehammer would be for Calibre to always remove the "current_position" entry for any book that it replaces, but that also removes where you're up to if the location in "current_position" is still valid which would be annoying. The correct thing would be for the reader itself to behave the way I recall the PRS-350 working - if it's confused, just go to the start of the book instead of putting up an error.

Cheers,
Simon.

04-02-2012, 11:04 PM	#6
snarkophilus Wannabe Connoisseur Posts: 426 Karma: 2516674 Join Date: Apr 2011 Location: Geelong, Australia Device: Kobo Libra 2, Kobo Aura 2, Sony PRS-T1, Sony PRS-350, Palm TX	I've also seen an error (sorry, I don't recall the exact wording but I think it might be "invalid page") on my T1 when I try to re-open a book after I modify it (in say Sigil). I've tracked this down to the entry for the book in the "current_position" table in books.db on the device pointing to an invalid location. The actual location in the book is stored as a reference like "OEBPS/Text/asimov-youthebook-3.html#point(/1/4/104/1:252)" and if that position no longer valid you get the error with no way to recover on the reader itself. There's two ways around this. First, as carpetmojo said, just delete the book from the reader and reload. The second is to use one of the SQLite tools and find your book's ID in the "books" table in the books.db, then delete the entry for that ID that from the "current_position" (remembering that the book ID column is called "content_id" in the "current_position" table). Needless to say I usually use the first option . I think, but am not sure, that my old PRS-350 simply went back to the start of the book if it got confused by where it thought your current position was rather than this annoying behaviour on the T1. I've been thinking of raising a feature request in Calibre to handle this, but I'm still not sure what the right thing to do is. The sledgehammer would be for Calibre to always remove the "current_position" entry for any book that it replaces, but that also removes where you're up to if the location in "current_position" is still valid which would be annoying. The correct thing would be for the reader itself to behave the way I recall the PRS-350 working - if it's confused, just go to the start of the book instead of putting up an error. Cheers, Simon.