rpcbuf - streambuf specialized for sending and receiving RPC requests

rpcbuf(iostreamb*=nil)
              Construct  an unopened rpcbuf, giving it a pointer to an iostreamb so that the rpcbuf can read and
              write the length field of RPC requests.

       An  rpcbuf  is  a  streambuf  specialized  in  two  ways: to use an IPC connection as a source or sink of
       characters and to send and receive RPC requests.  The rpcbuf encloses RPC requests in packets which begin
       with a length field so that the rpcbuf can buffer requests until they are complete if the user uses  non-
       blocking I/O.

constchar*host()intport()intfd()booleanopened()booleannonblocking()
              Return information about the IPC connection.

       enum{anyport=0}rpcbuf*listen(intport)
              Create a socket, bind the socket to a <localhost, port> address, and prepare  to  accept  incoming
              connections.  anyport can be used in place of a specific port number.  Return the rpcbuf's address
              if successful, nil otherwise.

       rpcbuf*connect(constchar*host,intport)
              Create a socket and connect it to a peer at the <host, port> address.  Return the rpcbuf's address
              if successful, nil otherwise.

       rpcbuf*accept(int&fd)
              Accept  an  incoming  connection,  allocate  a new file descriptor for it, and assign the new file
              descriptor to the parameter.  Return the rpcbuf's address if successful, nil  otherwise.   Can  be
              called only for rpcbufs that have already called listen.

       rpcbuf*attach(intfd)
              Attach  the  rpcbuf  to  a  file  descriptor.   The  rpcbuf  will not be allowed to close the file
              descriptor.

       rpcbuf*nonblocking(boolean)
              Enable or disable non-blocking I/O on the file descriptor (disabled by default).

       rpcbuf*verbose(boolean)
              Enable or disable printing of error messages when anything goes wrong (enabled by default).

       rpcbuf*close()
              Flush the get and put areas, close the file descriptor if it was created by the rpcbuf, and detach
              the rpcbuf from the file descriptor.

       rpcbuf - streambuf specialized for sending and receiving RPC requests

intstart_request()
              If a current request exists, compute its length and insert the length into  the  request's  length
              field.   Then  start  a  new  request,  making sure to leave space for the request's length field.
              Return 0 if no problem occurred, EOF otherwise.

       intread_request()
              Return 0 if a complete request is buffered in the get area, EOF otherwise.  The rpcbuf  moves  the
              get  pointer  back  to the beginning of the request after extracting the length field and checking
              that the get area contains that many bytes.

       IOS.INTRO(3C++), rpcstream(3I)

InterViews                                        27 March 1991                                       rpcbuf(3I)

virtualintoverflow(intc=EOF)
              If given EOF, terminate the current request.  Flush all requests buffered in the put  area  except
              for  the  last  request  if  it's  still  incomplete.   Shift  any still incomplete request to the
              beginning of the put area.  If given a character, append it to the request.

       virtualintunderflow()
              Flush the put area.  Shift any still unread or incomplete requests to the  beginning  of  the  get
              area  and  position  the  get  pointer  at  the  beginning  of the get area.  Read as much data as
              available to fill the rest of the get area.  Return the get area's first character  or  EOF  if  a
              problem occurred.

       virtualintsync()
              Discard  any  still  unread  requests from the get area.  Flush all buffered requests from the put
              area.

       virtualstreamposseekoff(streamoff,ios::seek_dir,int)
              Allow the user to find the get pointer's current position so the user can compute how  many  bytes
              the  get pointer moved between calls to seekoff.  Return EOF if the user tries to do anything else
              than find the get pointer's current position.

       virtualstreambuf*setbuf(char*,int)
              Reject any attempt to set the buffer used to store incoming and  outgoing  requests.   The  rpcbuf
              dynamically  allocates  separate  buffers  for  both  areas  and automatically resizes the buffers
              whenever necessary.

#include<Dispatch/rpcbuf.h>