NAME¶
MPI_Testall - Tests for the completion of all previously initiated
communications in a list.
SYNTAX¶
C Syntax¶
#include <mpi.h>
int MPI_Testall(int count, MPI_Request *array_of_requests,
int *flag, MPI_Status *array_of_statuses)
Fortran Syntax¶
INCLUDE 'mpif.h'
MPI_TESTALL( COUNT, ARRAY_OF_REQUESTS, FLAG, ARRAY_OF_STATUSES,
IERROR)
LOGICAL FLAG
INTEGER COUNT, ARRAY_OF_REQUESTS(*)
INTEGER ARRAY_OF_STATUSES(MPI_STATUS_SIZE,*), IERROR
C++ Syntax¶
#include <mpi.h>
static bool Request::Testall(int count, Request
array_of_requests[], Status array_of_statuses[])
static bool Request::Testall(int count, Request array_of_requests[])
- count
- Lists length (integer).
- array_of_requests
- Array of requests (array of handles).
OUTPUT PARAMETERS¶
- flag
- True if previously initiated communications are complete
(logical.)
- array_of_statuses
- Array of status objects (array of status).
- IERROR
- Fortran only: Error status (integer).
DESCRIPTION¶
Returns
flag = true if all communications associated with active handles
in the array have completed (this includes the case where no handle in the
list is active). In this case, each status entry that corresponds to an active
handle request is set to the status of the corresponding communication; if the
request was allocated by a nonblocking communication call then it is
deallocated, and the handle is set to MPI_REQUEST_NULL. Each status entry that
corresponds to a null or inactive handle is set to empty.
Otherwise,
flag = false is returned, no request is modified and the
values of the status entries are undefined. This is a local operation.
If your application does not need to examine the
array_of_statuses field,
you can save resources by using the predefined constant MPI_STATUSES_IGNORE
can be used as a special value for the
array_of_statuses argument.
Errors that occurred during the execution of MPI_Testall are handled in the same
manner as errors in MPI_Waitall.
NOTE¶
flag is true only if all requests have completed. Otherwise,
flag
is false, and neither
array_of_requests nor
array_of_statuses is
modified.
ERRORS¶
For each invocation of MPI_Testall, if one or more requests generate an MPI
exception, only the
first MPI request that caused an exception will be
passed to its corresponding error handler. No other error handlers will be
invoked (even if multiple requests generated exceptions). However,
all
requests that generate an exception will have a relevant error code set in the
corresponding status.MPI_ERROR field (unless MPI_STATUSES_IGNORE was used).
The default error handler aborts the MPI job, except for I/O function errors.
The error handler may be changed with MPI_Comm_set_errhandler,
MPI_File_set_errhandler, or MPI_Win_set_errhandler (depending on the type of
MPI handle that generated the MPI request); the predefined error handler
MPI_ERRORS_RETURN may be used to cause error values to be returned. Note that
MPI does not guarantee that an MPI program can continue past an error.
If the invoked error handler allows MPI_Testall to return to the caller, the
value MPI_ERR_IN_STATUS will be returned in the C and Fortran bindings. In
C++, if the predefined error handler MPI::ERRORS_THROW_EXCEPTIONS is used, the
value MPI::ERR_IN_STATUS will be contained in the MPI::Exception object. The
MPI_ERROR field can then be examined in the array of returned statuses to
determine exactly which request(s) generated an exception.
SEE ALSO¶
MPI_Comm_set_errhandler
MPI_File_set_errhandler
MPI_Test
MPI_Testany
MPI_Testsome
MPI_Wait
MPI_Waitall
MPI_Waitany
MPI_Waitsome
MPI_Win_set_errhandler