MPI_Unpack

Unpack a datatype into contiguous memory

Synopsis

#include "mpi.h"
int MPI_Unpack ( inbuf, insize, position, outbuf, outcount, datatype, comm )
void         *inbuf;
int           insize;
int          *position;
void         *outbuf;
int           outcount;
MPI_Datatype  datatype;
MPI_Comm      comm;

Input Parameters

	inbuf	input buffer start (choice)
	insize	size of input buffer, in bytes (integer)
	position	current position in bytes (integer)
	outcount	number of items to be unpacked (integer)
	datatype	datatype of each output data item (handle)
	comm	communicator for packed message (handle)

Output Parameter

outbuf

output buffer start (choice)

Notes for Fortran

All MPI routines in Fortran (except for MPI_WTIME and MPI_WTICK) have an additional argument ierr at the end of the argument list. ierr is an integer and has the same meaning as the return value of the routine in C. In Fortran, MPI routines are subroutines, and are invoked with the call statement.

All MPI objects (e.g., MPI_Datatype, MPI_Comm) are of type INTEGER in 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 last argument. Before the value is returned, the current MPI error handler is called. By default, this error handler aborts the MPI job. The error handler may be changed with MPI_Errhandler_set; the predefined error handler MPI_ERRORS_RETURN may be used to cause error values to be returned. Note that MPI does not guarentee that an MPI program can continue past an 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_ARG

Invalid argument. Some argument is invalid and is not identified by a specific error class (e.g., MPI_ERR_RANK).

See Also

MPI_Pack, MPI_Pack_size

Location:unpack.c