17.2.241. MPI_Is_thread_main
MPI_Is_thread_main - Determines if thread called MPI_Init
17.2.241.1. SYNTAX
17.2.241.1.1. C Syntax
#include <mpi.h>
int MPI_Is_thread_main(int *flag)
17.2.241.1.2. Fortran Syntax
USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_IS_THREAD_MAIN(FLAG, IERROR)
LOGICAL FLAG
INTEGER IERROR
17.2.241.1.3. Fortran 2008 Syntax
USE mpi_f08
MPI_Is_thread_main(flag, ierror)
LOGICAL, INTENT(OUT) :: flag
INTEGER, OPTIONAL, INTENT(OUT) :: ierror
17.2.241.2. OUTPUT PARAMETERS
flag
: True if calling thread is main thread (boolean).IERROR
: Fortran only: Error status (integer).
17.2.241.3. DESCRIPTION
MPI_Is_thread_main is called by a thread to find out whether the caller is the main thread (that is, the thread that called MPI_Init or MPI_Init_thread).
17.2.241.4. ERRORS
Almost all MPI routines return an error value; C routines as the value of the function and Fortran routines in the last argument.
Before the error value is returned, the current MPI error handler is called. By default, this error handler aborts the MPI job, except for I/O function errors. The error handler may be changed with MPI_Comm_set_errhandler; 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.
See the MPI man page for a full list of MPI error codes.
See also