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MPI_T_init_thread(3) MPI MPI_T_init_thread(3)

NAME

MPI_T_init_thread - Initialize the MPI_T execution environment

SYNOPSIS



int MPI_T_init_thread(int required, int *provided)










INPUT PARAMETERS



  

  
- desired level of thread support (integer)
    

  








OUTPUT PARAMETERS



  

  
- provided level of thread support (integer)
    

  








NOTES






THE VALID VALUES FOR THE LEVEL OF THREAD SUPPORT ARE



  

  
- Only one thread will execute.

  

  
- The process may be multi-threaded, but only the main thread will make
      MPI_T calls (all MPI_T calls are funneled to the main thread).

  

  
- The process may be multi-threaded, and multiple threads may make MPI_T
      calls, but only one at a time: MPI_T calls are not made concurrently from
      two distinct threads (all MPI_T calls are serialized).

  

  
- Multiple threads may call MPI_T, with no restrictions.
    

  








THREAD AND INTERRUPT SAFETY


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.








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_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 guarantee that an MPI
    program can continue past an error; however, MPI implementations will
    attempt to continue whenever possible.





  

  
- No error; MPI routine completed successfully.

  

  
- Invalid use of the interface or bad parameter values(s).

  

  
- Other error; use MPI_Error_string to get more information about
      this error code.
    

  








SEE ALSO


MPI_T_finalize







  

    2/9/2024