Oracle OCI interface (column types)

For various reasons, I am using Oracle's OCI interface to C. What I want to be able to do is to select certain columns from a table, Determine the types of those columns, and typecast a void * to the appropriate type. This makes it very easy to select data, as everything gets worked out automatically. However, as far as I can see, there are only two types stored by Oracle - NUMBER and CHAR. Is there any way of resolving these to a more direct correlation between these and C types (float, double, short, int, long etc) ?
Previous to this I have only used Ingres which keeps a lot more types which are analogous to C variables.

Cheers,
david

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