NAME

       RpcHdr - header for remote procedure calls

SYNOPSIS

       #include <Dispatch/rpchdr.h>

DESCRIPTION

       An  RpcHdr  enables  an  RPC request to be sent or received.  To send an RPC request, you would insert an
       RpcHdr into an rpcstream followed by any arguments and then flush the rpcstream if you wanted the request
       to be sent immediately.  The rpcstream automatically fills  in  each  RPC  request's  length  field.   To
       receive  an  RPC  request,  you  would  extract an RpcHdr from an rpcstream and examine the ``request()''
       member to determine which additional arguments need to  be  extracted  as  well.   You  can  examine  the
       ``ndata()'' member too if you need to estimate how much space to allocate.

CONSTRUCTORS

       RpcHdr(void* writer, int request)
       RpcHdr(int request)
       RpcHdr()
              Construct  an initialized header for an outgoing RPC request (first two constructors) or construct
              an uninitialized header for an incoming  RPC  request  (third  constructor).   To  initialize  the
              header, you'll have to store the request's protocol number.  You can also store the address of the
              writer  sending  the  RPC request if you want to route the RPC request to a specific reader on the
              peer's side.

PUBLIC OPERATIONS

       unsigned long reader()
       int request()
       unsigned int ndata()
              Get information about the RPC request.  ``reader()'' identifies the reader which should handle the
              RPC request.  ``request()'' identifies the action that should be performed.  ``ndata()'' gives the
              number of data bytes following the header, which may be useful for estimating the amount of  space
              that must be allocated to store an argument.

SEE ALSO

       RpcReader(3I), RpcWriter(3I), rpcstream(3I)

InterViews                                        27 March 1991                                       RpcHdr(3I)