[tex-k] How to get filehandle when `E'

[Igor Liferenko]

> I need an example how opening editor is done by
> querying alpha_file - the way it is supposed to work with this code:

To be more exact: How name of file is obtained from open file handle.

This is a quote from Karl's email:

In practice, the idea on the TOPS-20 systems where TeX was developed was
that an open alpha_file could be (and indeed had to be) queried to get
the filename.