MPI_T_CVAR_WRITE(3)				     Open MPI				       MPI_T_CVAR_WRITE(3)

MPI_T_cvar_write — Write the value of a bound control variable

SYNTAX
   C Syntax
	  #include <mpi.h>

	  int MPI_T_cvar_write(MPI_T_cvar_handle handle, const void *buf)

INPUT PARAMETERS
       • handle: Handle of the control variable to be written.

       • buf: Initial address of storage location for variable value.

DESCRIPTION
       MPI_T_cvar_write	 sets the value the control variable identified by the handle specified in handle from the
       buffer provided in buf. The caller must ensure that the buffer specified in buf is large enough to hold the
       entire value of the control variable. If the variable has global scope, any write call must  be	issued	on
       all connected MPI processes. For more information see MPI-3 section 14.3.6.

ERRORS
       MPI_T_cvar_write will fail if:

       • MPI_T_ERR_NOT_INITIALIZED: The MPI Tools interface not initialized

       • MPI_T_ERR_INVALID_HANDLE: The handle is invalid

       • MPI_T_ERR_CVAR_SET_NOT_NOW: Variable cannot be set at this moment

       • MPI_T_ERR_CVAR_SET_NEVER: Variable cannot be set until end of execution

       See also:

	  • MPI_T_cvar_handle_alloc <#mpi-t-cvar-handle-alloc>

	  • MPI_T_cvar_get_info <#mpi-t-cvar-get-info>

Copyright
       2003-2026, The Open MPI Community

						   Mar 05, 2026				       MPI_T_CVAR_WRITE(3)
