DBTCP driver functions for PHP4
For all the functions if 'link_identifier' isn't specified, the last opened link is assumed.

int dbtcp_connect ( string DSN, string host [ , int port ] )
Connect to the remote host 'host' and select the data source 'DSN'
Returns the link_identifier or FALSE to indicate whether or not the connection succeeded.

string dbtcp_error ( [ int link_identifier ] )
Returns the error message of the selected link.

int dbtcp_sql ( string QUERY [ , int link_identifier ] )
Sends a query to the server that's associated with the specified link identifier.
Returns TRUE (non-zero) or FALSE to indicate whether or not the query succeeded.

int dbtcp_num_fields ( [ int link_identifier )
Returns the number of fields in a result set.

array dbtcp_field_info( int field [, link_identifier] )
Returns an array that contains name,type and length of the field-th field.

array dbtcp_fetch ( [ int link_identifier ] )
Returns an array that corresponds to the fetched row, or FALSE if there are no more rows.

dbtcp_close ( [ int link_indetifier ] )
Close the connection that's associated with the specified link identifier.