MPI_Buffer_detach

--- Removes an existing buffer (for use in MPI_Bsend etc)

Output Parameters

buffer: initial buffer address (choice)

size: buffer size, in bytes (integer)

Notes

The reason that MPI_Buffer_detach returns the address and size of the buffer being detached is to allow nested libraries to replace and restore the buffer. For example, consider

int size, mysize, idummy;
void *ptr, *myptr, *dummy;
MPI_Buffer_detach( ∧ptr, ∧size );
MPI_Buffer_attach( myptr, mysize );
...
... library code ...
...
MPI_Buffer_detach( ∧dummy, ∧idummy );
MPI_Buffer_attach( ptr, size );
This is much like the action of the Unix signal routine and has the same strengths (its simple) and weaknesses (it only works for nested usages).

Notes for Fortran

The Fortran binding for this routine is different. Because Fortran does not have pointers, it is impossible to provide a way to use the output of this routine to exchange buffers. In this case, only the size field is set.

Synopsis


#include "mpi.h"
int MPI_Buffer_detach( buffer, size )
void **buffer;
int  *size;

Location: buffree.c