.\" Man page generated from reStructuredText. . .TH "MPI_REGISTER_DATAREP" "3" "Apr 08, 2024" "" "Open MPI" . .nr rst2man-indent-level 0 . .de1 rstReportMargin \\$1 \\n[an-margin] level \\n[rst2man-indent-level] level margin: \\n[rst2man-indent\\n[rst2man-indent-level]] - \\n[rst2man-indent0] \\n[rst2man-indent1] \\n[rst2man-indent2] .. .de1 INDENT .\" .rstReportMargin pre: . RS \\$1 . nr rst2man-indent\\n[rst2man-indent-level] \\n[an-margin] . nr rst2man-indent-level +1 .\" .rstReportMargin post: .. .de UNINDENT . RE .\" indent \\n[an-margin] .\" old: \\n[rst2man-indent\\n[rst2man-indent-level]] .nr rst2man-indent-level -1 .\" new: \\n[rst2man-indent\\n[rst2man-indent-level]] .in \\n[rst2man-indent\\n[rst2man-indent-level]]u .. .sp \fI\%MPI_Register_datarep\fP — Defines data representation. .SH SYNTAX .SS C Syntax .INDENT 0.0 .INDENT 3.5 .sp .nf .ft C #include int MPI_Register_datarep(const char *datarep, MPI_Datarep_conversion_function *read_conversion_fn, MPI_Datarep_conversion_function *write_conversion_fn, MPI_Datarep_extent_function *dtype_file_extent_fn, void *extra_state) .ft P .fi .UNINDENT .UNINDENT .SS Fortran Syntax .INDENT 0.0 .INDENT 3.5 .sp .nf .ft C USE MPI ! or the older form: INCLUDE \(aqmpif.h\(aq MPI_REGISTER_DATAREP(DATAREP, READ_CONVERSION_FN, WRITE_CONVERSION_FN, DTYPE_FILE_EXTENT_FN, EXTRA_STATE, IERROR) CHARACTER*(*) DATAREP EXTERNAL READ_CONVERSION_FN, WRITE_CONVERSION_FN, DTYPE_FILE_EXTENT_FN INTEGER IERROR INTEGER(KIND=MPI_ADDRESS_KIND) EXTRA_STATE .ft P .fi .UNINDENT .UNINDENT .SS Fortran 2008 Syntax .INDENT 0.0 .INDENT 3.5 .sp .nf .ft C USE mpi_f08 MPI_Register_datarep(datarep, read_conversion_fn, write_conversion_fn, dtype_file_extent_fn, extra_state, ierror) CHARACTER(LEN=*), INTENT(IN) :: datarep PROCEDURE(MPI_Datarep_conversion_function) :: read_conversion_fn PROCEDURE(MPI_Datarep_conversion_function) :: write_conversion_fn PROCEDURE(MPI_Datarep_extent_function) :: dtype_file_extent_fn INTEGER(KIND=MPI_ADDRESS_KIND), INTENT(IN) :: extra_state INTEGER, OPTIONAL, INTENT(OUT) :: ierror .ft P .fi .UNINDENT .UNINDENT .SH INPUT PARAMETERS .INDENT 0.0 .IP \(bu 2 \fBdatarep\fP: Data representation identifier (string). .IP \(bu 2 \fBread_conversion_fn\fP: Function invoked to convert from file representation to native representation (function). .IP \(bu 2 \fBwrite_conversion_fn\fP: Function invoked to convert from native representation to file representation (function). .IP \(bu 2 \fBdtype_file_extent_fn\fP: Function invoked to get the extent of a data type as represented in the file (function). .IP \(bu 2 \fBextra_state\fP: Extra state. .UNINDENT .SH OUTPUT PARAMETER .INDENT 0.0 .IP \(bu 2 \fBierror\fP: Fortran only: Error status (integer). .UNINDENT .SH DESCRIPTION .sp \fI\%MPI_Register_datarep\fP defines a data representation. It associates the data representation’s identifier (a string) with the functions that convert from file representation to the native representation and vice versa, with the function that gets the extent of a data type as represented in the file, as well as with “extra state,” which is used for passing arguments. Once a data representation has been registered using this routine, you may specify its identifier as an argument to \fI\%MPI_File_set_view\fP, causing subsequent data\-access operations to call the specified conversion functions. .sp The call associates \fIread_conversion_fn\fP, \fIwrite_conversion_fn\fP, and \fIdtype_file_extent_fn\fP with the data representation identifier \fIdatarep\fP\&. \fIdatarep\fP can then be used as an argument to \fI\%MPI_File_set_view\fP, causing subsequent data access operations to call the conversion functions to convert all data items accessed between file data representation and native representation. \fI\%MPI_Register_datarep\fP is a local operation and only registers the data representation for the calling MPI process. If \fIdatarep\fP is already defined, an error in the error class MPI_ERR_DUP_DATAREP is raised using the default file error handler. The length of a data representation string is limited to the value of MPI_MAX_DATAREP_STRING. MPI_MAX_DATAREP_STRING must have a value of at least 64. No routines are provided to delete data representations and free the associated resources; it is not expected that an application will generate them in significant numbers. .SH NOTES .sp The Fortran version of each MPI I/O routine includes a final argument, IERROR, which is not defined in the PARAMETERS sections. This argument is used to return the error status of the routine in the manner typical for Fortran library routines. .sp The C version of each routine returns an error status as an integer return value. .sp Error classes are found in mpi.h (for C) and mpif.h (for Fortran). .SH ERRORS .sp Almost all MPI routines return an error value; C routines as the return result of the function and Fortran routines in the last argument. .sp Before the error value is returned, the current MPI error handler associated with the communication object (e.g., communicator, window, file) is called. If no communication object is associated with the MPI call, then the call is considered attached to MPI_COMM_SELF and will call the associated MPI error handler. When MPI_COMM_SELF is not initialized (i.e., before \fI\%MPI_Init\fP/\fI\%MPI_Init_thread\fP, after \fI\%MPI_Finalize\fP, or when using the Sessions Model exclusively) the error raises the initial error handler. The initial error handler can be changed by calling \fI\%MPI_Comm_set_errhandler\fP on MPI_COMM_SELF when using the World model, or the mpi_initial_errhandler CLI argument to mpiexec or info key to \fI\%MPI_Comm_spawn\fP/\fI\%MPI_Comm_spawn_multiple\fP\&. If no other appropriate error handler has been set, then the MPI_ERRORS_RETURN error handler is called for MPI I/O functions and the MPI_ERRORS_ABORT error handler is called for all other MPI functions. .sp Open MPI includes three predefined error handlers that can be used: .INDENT 0.0 .IP \(bu 2 \fBMPI_ERRORS_ARE_FATAL\fP Causes the program to abort all connected MPI processes. .IP \(bu 2 \fBMPI_ERRORS_ABORT\fP An error handler that can be invoked on a communicator, window, file, or session. When called on a communicator, it acts as if \fI\%MPI_Abort\fP was called on that communicator. If called on a window or file, acts as if \fI\%MPI_Abort\fP was called on a communicator containing the group of processes in the corresponding window or file. If called on a session, aborts only the local process. .IP \(bu 2 \fBMPI_ERRORS_RETURN\fP Returns an error code to the application. .UNINDENT .sp MPI applications can also implement their own error handlers by calling: .INDENT 0.0 .IP \(bu 2 \fI\%MPI_Comm_create_errhandler\fP then \fI\%MPI_Comm_set_errhandler\fP .IP \(bu 2 \fI\%MPI_File_create_errhandler\fP then \fI\%MPI_File_set_errhandler\fP .IP \(bu 2 \fI\%MPI_Session_create_errhandler\fP then \fI\%MPI_Session_set_errhandler\fP or at \fI\%MPI_Session_init\fP .IP \(bu 2 \fI\%MPI_Win_create_errhandler\fP then \fI\%MPI_Win_set_errhandler\fP .UNINDENT .sp Note that MPI does not guarantee that an MPI program can continue past an error. .sp See the \fI\%MPI man page\fP for a full list of \fI\%MPI error codes\fP\&. .sp See the Error Handling section of the MPI\-3.1 standard for more information. .SH COPYRIGHT 2003-2024, The Open MPI Community .\" Generated by docutils manpage writer. .