I followed this tutorial to create an epub file. The mimetype file only contains application/epub+zip and should not be compressed. However, the zip commands that were recommended to achieve the non-compression of mimetype, i. e.
zip -0Xq ebook.epub mimetype zip -Xr9Dq ebook.epub *
...produce the following error when I run epubcheck:
ERROR: ebook.epub/mimetype: Mimetype file should contain only the string "application/epub+zip".
So I tried two other combinations of zip options, but the error stays the same.
zip -X ebook.epub mimetype zip -rg ebook.epub META-INF zip -rg ebook.epub OEBPS zip -X0 ebook.epub mimetype zip -rX9 ebook.epub * -x mimetype
However, Calibre will open any of these Ebooks without any problems.
The content of my mimetype file is correct, so that it must be a problem with the zip commands. Or could this a bug of epubcheck?