SETRBUF(3PVM)							SETRBUF(3PVM)

NAME
  pvm_setrbuf -	Switches the active receive buffer and saves the previous
  buffer.

SYNOPSIS
  C	  int oldbuf = pvm_setrbuf( int	bufid )

  Fortran call pvmfsetrbuf( bufid, oldbuf )

PARAMETERS

  bufid	  Integer specifying the message buffer	identifier for the new active
	  receive buffer.

  oldbuf  Integer returning the	message	buffer identifier for the previous
	  active receive buffer.

DISCUSSION
  The routine pvm_setrbuf switches the active receive buffer to	bufid and
  saves	the previous active receive buffer oldbuf. If bufid is set to 0	then
  the present active receive buffer is saved and no active receive buffer
  exists.

  A successful receive automatically creates a new active receive buffer.  If
  a previous receive has not been unpacked and needs to	be saved for later,
  then the previous bufid can be saved and reset later to the active buffer
  for unpacking.

  The routine is required when managing	multiple message buffers.  For exam-
  ple switching	back and forth between two buffers.  One buffer	could be used
  to send information to a graphical interface while a second buffer could be
  used send data to other tasks	in the application.

EXAMPLES
  C:
	  rbuf1	= pvm_setrbuf( rbuf2 );

  Fortran:
	  CALL PVMFSETRBUF( NEWBUF, OLDBUF )

ERRORS
  These	error conditions can be	returned by pvm_setrbuf
       PvmBadParam    giving an	invalid	bufid.
       PvmNoSuchBuf   switching	to a non-existent message buffer.

SEE ALSO
  pvm_setsbuf(3PVM)