MPIX_Igatherv - XXX description here
int MPIX_Igatherv(const void *sendbuf, int sendcount, MPI_Datatype sendtype, void *recvbuf, const int *recvcounts, const int *displs, MPI_Datatype recvtype, int root, MPI_Comm comm, MPI_Request *request)
- sendbuf
- - starting address of the send buffer (choice)
- sendcount
- - number of elements in send buffer (non-negative integer)
- sendtype
- - data type of send buffer elements (handle)
- recvcounts
- - non-negative integer array (of length group size) containing the number
of elements that are received from each process (significant only at
root)
- displs
- - integer array (of length group size). Entry i specifies the displacement
relative to recvbuf at which to place the incoming data from process i
(significant only at root)
- recvtype
- - data type of receive buffer elements (significant only at root)
(handle)
- root
- - rank of receiving process (integer)
- comm
- - communicator (handle)
- recvbuf
- - starting address of the receive buffer (significant only at root)
(choice)
- request
- - communication request (handle)
This routine is thread-safe. This means that this routine may be safely used by
multiple threads without the need for any user-provided thread locks. However,
the routine is not interrupt safe. Typically, this is due to the use of memory
allocation routines such as malloc or other non-MPICH runtime routines
that are themselves not interrupt-safe.
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.
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_Comm_set_errhandler (for communicators),
MPI_File_set_errhandler (for files), and MPI_Win_set_errhandler
(for RMA windows). The MPI-1 routine MPI_Errhandler_set may be used but
its use is deprecated. 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; however,
MPI implementations will attempt to continue whenever possible.