MPISUCCESS

MPISUCCESS refers to the success status used in the Message Passing Interface (MPI) ecosystem. In the formal MPI standard, the canonical symbol is MPI_SUCCESS, a predefined integer constant that indicates a routine completed without error. Some code bases or older documentation may colloquially refer to it as MPISUCCESS, but the standard name is MPI_SUCCESS.

Value and purpose: MPI_SUCCESS is defined as zero. It is returned by MPI routines to signal successful execution. Program logic often checks the return value of MPI functions against MPI_SUCCESS to detect errors, rather than relying on silent failures. If a function returns a value different from MPI_SUCCESS, an error has occurred and MPI’s error handling mechanisms are invoked.

Usage in practice: After calling an MPI function, typical code tests whether the result equals MPI_SUCCESS. If not, error handling is engaged, which might involve reporting the error, terminating the program, or invoking a user-defined error handler. MPI provides facilities such as MPI_Error_string to convert error codes into readable messages and MPI_Errhandler_set to customize error handling behavior. The default error handler may abort the program or print an error message, depending on the MPI implementation and configuration.

Portability and standards: All MPI implementations define MPI_SUCCESS, and it is guaranteed to be zero. MPI uses a uniform error reporting model across C, C++, and Fortran bindings, with MPI_SUCCESS serving as the baseline indicator of a non-error condition.

Notes: MPISUCCESS is not the official MPI name, though some non-standard references might use it. For portable MPI code, always compare against MPI_SUCCESS as defined by the MPI headers. See also MPI, MPI_ERROR, and MPI_Errhandler.