10.5. Error Classes, Error Codes, and Error Handlers

Users may want to write a layered library on top of an existing MPI implementation, and this library may have its own set of error codes and classes. An example of such a library is an I/O library based on MPI, see Chapter I/O. For this purpose, functions are needed to:

1. add a new error class and remove previously added user-defined error classes;
2. associate error codes with this error class, so that MPI_ERROR_CLASS works;
3. associate strings with these error codes, so that MPI_ERROR_STRING works;
4. remove such associations;
5. invoke the error handler associated with a communicator, window, file, or session object.