Communicator e3000 MPE/iX Release 7.0 Express 1 (Software Release C.70.01) (30216-90328)

114 Chapter5
Technical Articles
DCE to RPC 1.2.1
DCE to RPC 1.2.1
Commercial Systems Division
DCE RPC is the software to implement the communication between the client and server
of an application through the Remote Procedure call (RPC). RPC gives the users the ability
to express an interaction between client and server of a distributed application as if it were
a procedure call. RPC provides a high-level programming model to the distributed
applications and hides networking communication details from the users.
DCE RPC consists of several RPC components that work together to provide the
communication between client and server under the distributed computing environment.
The major components of RPC include:
• The interface definition language (IDL) and its compiler
• RPC Daemon (an RPC specific name server manages the mapping between RPC server
to the transport endpoints)
• the RPC runtime library, which implements the communication between the client and
server sides
Deliverables
The deliverables for RPC 1.2.1 are:
• /lib/libdce.sl
• IDL - Compiler
• The catalog files
The applications developed in the MPE/iX environment and linking to the
DCEXL.HPDCE.SYS library will be using 1.0.2 APIs. The 1.2.1 version of DCE library is
delivered in POSIX environment as /usr/lib/libdce.sl. So any application linking to this
library will use 1.2.1 APIs.
Threads Changes
One of the major changes during the porting of RPC 1.2.1 is that of the thread
functionality. From RPC 1.2.1 onwards threads library components are separated from
DCEXL (the DCE executable library). It means that the end-user can write thread related
application without linking to DCEXL. The thread library now is delivered and supported
by the Process Management Group in CSY as /usr/lib/libpthread.sl. The new library for
threads support only POSIX threads standard, also known as Draft10 standard.
To use the new thread library, the RPC 1.2.1 component is also moved to POSIX threads
standard. RPC 1.2.1 uses POSIX thread implementations. RPCD and RPCCP are not
delivered with RPC 1.2.1; they are part of 1.0.2 version only, using the DCE thread APIs.
System Environment Requirement
The RPC 1.2.1 software can be used from MPE/iX release 6.0 onwards. RPC 1.2.1 software
was released as patches for MPE/iX 6.0 version. To use RPC 1.2.1, the system should be