MPI Programming Guide

Predefined error handler for C++

The C++ language interface for MPI includes the predefined error handler MPI::ERRORS_THROW_EXCEPTIONS for use with MPI::Comm::Set_errhandler, MPI::File::Set_errhandler, and MPI::Win::Set_errhandler. MPI::ERRORS_THROW_EXCEPTIONS can only be set or retrieved by C++ functions. If a non-C++ program causes an error that invokes the MPI::ERRORS_THROW_EXCEPTIONS error handler, the exception will pass up the calling stack until C++ code can catch it. If there is no C++ code to catch it, the behavior is undefined.

The error handler MPI::ERRORS_THROW_EXCEPTIONS causes an MPI::Exception to be thrown for any MPI result code other than MPI::SUCCESS.

The C++ bindings for exceptions follow:

namespace MPI [ 
 
Exception::Exception(int error_code); 
int Exception::Get_error_code() const; 
int Exception::Get_error_class() const; 
const char* Exception::Get_error_string() const; 
 
]; 

The public interface to MPI::Exception class is defined as follows:

namespace MPI [ 
  class Exception [ 
  public: 
 
Exception(int error_code);  
 
int Get_error_code() const; 
    int Get_error_class() const; 
    const char *Get_error_string() const; 
  ]; 
]; 

The PE MPI implementation follows:

public:
 
      Exception(int ec) : error_code(ec)
      [
        (void)MPI_Error_class(error_code, &error_class);
        int resultlen;
        (void)MPI_Error_string(error_code, error_string, &resultlen);
      ]
 
      virtual ~Exception(){ }
 
 
      virtual int Get_error_code() const
      [
        return error_code;
      ]
 
      virtual int Get_error_class() const
      [
        return error_class;
      ]
 
      virtual const char* Get_error_string() const
      [
        return error_string;
      ]
 
    protected:
 
      int  error_code;
      char error_string[MPI_MAX_ERROR_STRING];
      int  error_class;
 
  };