The default installation directory for Sybase ASE in windows is
C:sybase, so your interfaces (
should be located there.
For SQL Anywhere, the interfaces file is called
and it's location varies, but you should be able to do a search of your
system drive to find it.
For SQL Anywhere you probably want to use the PHP apis that are provide
by SAP Sybase. The SQL Anywhere documentation is a pretty good place to
start, as it covers all the pieces that need to be installed to get SQL
Anywhere to talk to PHP.
SQL Anywhere 11: SQL Anwhere PHP API
You may also be able to find good information over at the SAP
Community Network site for SQL Anywhere.