MPI_INFO_ENV(3)                    Open MPI                    MPI_INFO_ENV(3)


MPI_Info_env -- Static MPI_Info object containing info about the application

DESCRIPTION
       The MPI-3 standard established a static MPI_Info object named
       MPI_Info_env that can be used to access information about how the
       application was executed from the run-time.

SUPPORTED FIELDS

       command
              If available, the value will be set to argv[0]. Note that the
              value may not always be available - e.g., it is valid for a
              program to call MPI_Init with NULL parameters, in which case
              argv[0] will not be set if run as a singleton. This value will
              never be set in a Fortran program as the argv are not available.

       argv   The argv given for the application. If no arguments are passed
              to the application, then this value will not be set. It will
              also not be set in the case of a singleton that calls MPI_Init
              with NULL parameters, or a Fortran program.

       maxprocs
              The number of processes in the job.

       soft   Open MPI does not support the soft option for specifying the
              number of processes to be executed, so this value is set to the
              same as maxprocs.

       host   The name of the host this process is executing upon - the value
              returned from gethostname().

       arch   The architecture of the host this process is executing upon.
              This value indicates the underlying chip architecture (e.g.,
              x86_64), if it can be determined.

       wdir   The working directory at the time of process launch by mpiexec.
              Note that this value will not be set for processes launched as
              singletons as there is no reliable way for the MPI library to
              determine the location.

       file   Although specified by the MPI-3 standard, no value is currently
              set for this field.

       thread_level
              The requested MPI thread level - note that this may differ from
              the actual MPI thread level of the application.

       ompi_num_apps
              The number of application contexts in an MPMD job. This is an
              Open MPI-specific field and value.

       ompi_np
              The number of processes in each application context, provided as
              a space-delimited list of integers. This is an Open MPI-specific
              field and value.

       ompi_first_rank
              The MPI rank of the first process in each application context,
              provided as a space-delimited list of integers This is an Open
              MPI-specific field and value.

       ompi_positioned_file_dir
              If Open MPI was asked to pre-position files, this field provides
              the top-level directory where those files were place. This is an
              Open MPI-specific field and value.

ERRORS
       When calling MPI_Info_get, the flag parameter will be set to zero
       (false) if a value for the field has not been set.


       SEE ALSO:

          o MPI_Info_get

COPYRIGHT
       2003-2024, The Open MPI Community

                                 April 8, 2024                 MPI_INFO_ENV(3)