Abstract: The present invention concerns a device permitting the utilization of a remote procedure call of open systems employing the socket process in a proprietary application, utilizing primitives which do not exist in the proprietary system and running on a computer system which makes use of an open subsystem utilizing the socket, comprising: means for communicating between the proprietary application and an application of the open subsystem; means for coding the primitives of the proprietary application into a special format and storage of the primitives; means for launching an application under the open system (UNIX) to decode and execute the function called by the primitive and to return the result; means for decoding the result; means for ensuring the synchronization of the accesses to the shared memory.