How do I obtain a list of schemas that an Oracle user has access to

In Oracle I can grant privileges on my schema to another user so that the other user has access to my schema (and in turn objects in my schema).

How do I programmatically ,using ADO.NET (either MS or Oracle's provider), o开发者_JAVA百科btain a list of schemas to which a particular user has access?

If connected as the user of interest:

select distinct table_schema from all_tab_privs;