MPIL_Signal − LAM/MPI-specific function to send a LAM signal to a rank in an MPI communicator
int MPIL_Signal(MPI_Comm comm, int rank, int signo)
- MPI communicator (handle)
- rank to send it to
- signal number
An asynchronous signal is delivered from one process to another with MPIL_Signal(). The target process is selected with a communicator and a process rank within that communicator. The remaining argument, signo, identifies the signal to be delivered. These signals are completely apart from the signals provided by the underlying operating system. LAM signals, defined in <lam_ksignal.h>, are listed below.
LAM_SIGTRACE 1 unload trace data
LAM_SIGC 2 user defined
LAM_SIGARECV 3 async receive pending
LAM_SIGUDIE 4 terminate
LAM_SIGARREST 5 suspend execution
LAM_SIGRELEASE 6 continue execution
LAM_SIGA 7 user defined
LAM_SIGB 8 user defined
LAM_SIGFUSE 9 node about to die
LAM_SIGSHRINK 10 another node has died
This is a LAM/MPI-specific function. Most users should not have use for this function. If this function is used, it should be used in conjunction with the LAM_MPI C preprocessor macro
MPIL_Signal(MPI_COMM_WORLD, 0, LAM_SIGUDIE);
All MPI routines in Fortran (except for MPI_WTIME and MPI_WTICK ) have an additional argument ierr at the end of the argument list. ierr is an integer and has the same meaning as the return value of the routine in C. In Fortran, MPI routines are subroutines, and are invoked with the call statement.
All MPI objects (e.g., MPI_Datatype , MPI_Comm ) are of type INTEGER in Fortran.
If an error occurs in an MPI function, the current MPI error handler is called to handle it. By default, this error handler aborts the MPI job. The error handler may be changed with MPI_Errhandler_set ; the predefined error handler MPI_ERRORS_RETURN may be used to cause error values to be returned (in C and Fortran; this error handler is less useful in with the C++ MPI bindings. The predefined error handler MPI::ERRORS_THROW_EXCEPTIONS should be used in C++ if the error value needs to be recovered). Note that MPI does not guarantee that an MPI program can continue past an error.
All MPI routines (except MPI_Wtime and MPI_Wtick ) return an error value; C routines as the value of the function and Fortran routines in the last argument. The C++ bindings for MPI do not return error values; instead, error values are communicated by throwing exceptions of type MPI::Exception (but not by default). Exceptions are only thrown if the error value is not MPI::SUCCESS .
Note that if the MPI::ERRORS_RETURN handler is set in C++, while MPI functions will return upon an error, there will be no way to recover what the actual error value was.
- No error; MPI routine completed successfully.
- Invalid communicator. A common error is to use a null communicator in a call (not even allowed in MPI_Comm_rank ).
- Invalid source or destination rank. Ranks must be between zero and the size of the communicator minus one; ranks in a receive ( MPI_Recv , MPI_Irecv , MPI_Sendrecv , etc.) may also be MPI_ANY_SOURCE .
- Other error; use MPI_Error_string to get more information about this error code.