MPI_Sendrecv_replace
Sends and receives using a single buffer 
Synopsis
#include "mpi.h"
int MPI_Sendrecv_replace( buf, count, datatype, dest, sendtag, 
     source, recvtag, comm, status )
void         *buf;
int           count, dest, sendtag, source, recvtag;
MPI_Datatype  datatype;
MPI_Comm      comm;
MPI_Status   *status;
Input Parameters
|  | count | number of elements in send and receive buffer (integer) 
 | 
|  | datatype | type of elements in send and receive buffer (handle) 
 | 
|  | dest | rank of destination (integer) 
 | 
|  | sendtag | send message tag (integer) 
 | 
|  | source | rank of source (integer) 
 | 
|  | recvtag | receive message tag (integer) 
 | 
|  | comm | communicator (handle) 
 | 
Output Parameters
|  | buf | initial address of send and receive buffer (choice) 
 | 
|  | status | status object (Status) 
 | 
Notes for Fortran
All MPI routines in Fortran (except for MPI_WTIME and MPI_WTICK) 
havean additional argument ierr at the end of the argument list.  
ierris an integer and has the same meaning as the return value of the 
routinein C.  In Fortran, MPI routines are subroutines, and are invoked with 
thecall statement.
All MPI objects (e.g., MPI_Datatype, MPI_Comm) are of type 
INTEGERin Fortran.
Errors
All MPI routines (except MPI_Wtime and MPI_Wtick) return an error value;
C routines as the value of the function and Fortran routines in the 
lastargument.  Before the value is returned, the current MPI error handler 
iscalled.  By default, this error handler aborts the MPI job.  The error 
handlermay be changed with MPI_Errhandler_set; the predefined error 
handlerMPI_ERRORS_RETURN may be used to cause error values to be returned.
Note that MPI does not guarentee that an MPI program can continue 
pastan error.
- MPI_SUCCESS  
-  No error; MPI routine completed successfully.
- MPI_ERR_COMM  
-  Invalid communicator.  A common error is to use a null
communicator in a call (not even allowed in MPI_Comm_rank).
- MPI_ERR_COUNT  
-  Invalid count argument.  Count arguments must be 
non-negative; a count of zero is often valid.
- MPI_ERR_TYPE  
-  Invalid datatype argument.  May be an uncommitted 
MPI_Datatype (see MPI_Type_commit).
- MPI_ERR_TAG  
-  Invalid tag argument.  Tags must be non-negative; tags
in a receive (MPI_Recv, MPI_Irecv, MPI_Sendrecv, etc.) may
also be MPI_ANY_TAG.  The largest tag value is available through the 
the attribute MPI_TAG_UB.
- MPI_ERR_RANK  
-  Invalid source or destination rank.  Ranks must be between
zero and the size of the communicator minus one; ranks in a receive
(MPI_Recv, MPI_Irecv, MPI_Sendrecv, etc.) may also be MPI_ANY_SOURCE.
- MPI_ERR_TRUNCATE  
-  Message truncated on receive.  The buffer size specified
was too small for the received message.  This is a recoverable error in
the MPICH implementation.
- MPI_ERR_INTERN  
-  This error is returned when some part of the MPICH 
implementation is unable to acquire memory.  
Location:sendrecv_rep.c