/*
 * call-seq:
 *    res.fsize( index )
 *
 * Returns the size of the field type in bytes.  Returns <tt>-1</tt> if the field is variable sized.
 *
 *   res = conn.exec("SELECT myInt, myVarChar50 FROM foo")
 *   res.size(0) => 4
 *   res.size(1) => -1
 */
static VALUE
pgresult_fsize(VALUE self, VALUE index)
{
    PGresult *result;
    int i = NUM2INT(index);

    result = get_pgresult(self);
    if (i < 0 || i >= PQnfields(result)) {
        rb_raise(rb_eArgError,"invalid field number %d", i);
    }
    return INT2NUM(PQfsize(result, i));
}