1 Cache directory resembles the notes hierarchy. Each file corresponds to
2 the note file, keeping at least three lines: versioned magic number,
3 inode number and ctime value in seconds. All of that is used to
4 determine if note was changed and cache is valid.
6 All other lines contain the links present in the note.
8 Any change to the file leads to ctime changing and cache invalidation
9 with full parsing of the note.
11 If note's cache is valid, then also the part of HTML is also kept in
12 .html-file nearby. It contains all the data till closing <pre>-tag.
13 Links and backlinks are generated every time.