MPISendrecv

[Hasselin Xavier]

Hello,

I've a problem with MPISendRecv (in Fortran).  I want to use it in a 
loop, each time with  the same arguments (same successor,predecessor, 
buffer,...).  During the first pass, it works, but after I receive 
nothing (in fact MPISendrecv seems to be executed, but my receiving 
buffer is not modified).

    My outbuffer is well initialised (with some MPI_Packed), my 
predessecor,my successor too, I've check it.   
    My outbuffer and my inbuffer are defined in the same way.
    I use MPISendRecv like this :
        call 
MPI_Sendrecv(buffer_out,max_send,MPI_PACKED,successor,predecessor,0,buffer_in,
         max_send,MPI_PACKED,predecessor,communicator,status,error_code)
  
Can someone help me?

Thank you.

Xavier Hasselin