Is it possible to control how BibTeX reads the aux file?
As far as I know, BibTeX reads the citation keys used in a document via the
\citation commands in the aux file(s). I want BibTeX to extract from the aux file other information that can be used by the bst file. The aim is to customize each instance of
\cite, so that how an item appears in the bibliography not only depends on what the citation key is, but can also depend on how it was
\cited in the document. There may be other (dirtier?) ways to achieve this aim, but (for me) it is interesting to know whether this particular way is possible.