C Syntax

       2003-2025, The Open MPI Community

                                                  Jun 07, 2025                        MPI_T_CATEGORY_GET_INFO(3)

MPI_T_category_get_info can be used to query information from a category. The function returns the number
       of  control variables, performance variables, and sub-categories in the queried category in the arguments
       num_cvars, num_pvars, and num_categories, respectively.

MPI_T_category_get_info will fail if:

       • MPI_T_ERR_NOT_INITIALIZED: The MPI Tools interface not initialized

       • MPI_T_ERR_INVALID_INDEX: The category index is invalid

       • cat_index: Index of the category to be queried.

       • name_len: Length of the string and/or buffer for name.

       • desc_len: Length of the string and/or buffer for desc.

       This MPI tool interface function returns two strings. This function takes two argument for each string: a
       buffer to store the string, and a length which must initially specify the size  of  the  buffer.  If  the
       length  passed  is  n  then  this  function  will  copy  at  most n - 1 characters of the string into the
       corresponding buffer and set the length to the number of characters copied - 1. If the length argument is
       NULL or the value specified in the length is 0 the corresponding string buffer is ignored and the  string
       is not returned.

       • name: Buffer to return the string containing the name of the category.

       • desc: Buffer to return the string containing the description of the category.

       • num_cvars: Number of control variables in the category.

       • num_pvars: Number of performance variables in the category.

       • num_categories: Number of categories contained in the category.

CSyntax
          #include <mpi.h>

          int MPI_T_category_get_info(int cat_index, char *name, int *name_len,
          char *desc, int *desc_len, int *num_cvars, int *num_pvars,
          int *num_categories)