.\" Copyright 2010 Cisco Systems, Inc. All rights reserved. .\" Copyright 2006-2008 Sun Microsystems, Inc. .\" Copyright (c) 1996 Thinking Machines Corporation .TH MPI_Address 3 "#OMPI_DATE#" "#PACKAGE_VERSION#" "#PACKAGE_NAME#" .SH NAME \fBMPI_Address\fP \- Gets the address of a location in memory -- use of this routine is deprecated. .SH SYNTAX .ft R .SH C Syntax .nf #include int MPI_Address(void *\fIlocation\fP, MPI_Aint\fP *address\fP) .fi .SH Fortran Syntax .nf INCLUDE 'mpif.h' MPI_ADDRESS(\fILOCATION\fP,\fI ADDRESS\fP,\fI IERROR\fP) \fILOCATION\fP (*) INTEGER \fIADDRESS\fP,\fI IERROR\fP .fi .SH INPUT PARAMETER .ft R .TP 1i location Location in caller memory (choice). .SH OUTPUT PARAMETERS .ft R .TP 1i address Address of location (integer). .ft R .TP 1i IERROR Fortran only: Error status (integer). .SH DESCRIPTION .ft R Note that use of this routine is \fIdeprecated\fP as of MPI-2. Please use MPI_Get_address instead. .sp This deprecated routine is not available in C++. .sp The address of a location in memory can be found by invoking this function. Returns the (byte) address of location. .sp Example: Using MPI_Address for an array. .sp .nf REAL A(100,100) .fi .br INTEGER I1, I2, DIFF .br CALL MPI_ADDRESS(A(1,1), I1, IERROR) .br CALL MPI_ADDRESS(A(10,10), I2, IERROR) .br DIFF = I2 - I1 .br ! The value of DIFF is 909*sizeofreal; the values of I1 and I2 are .br ! implementation dependent. .fi .SH NOTES .ft R This routine is provided for both Fortran and C programmers and may be useful when writing portable code. In the current release, the address returned by this routine will be the same as that produced by the C & operator. .sp C users may be tempted to avoid using MPI_Address and rely on the availability of the address operator &. Note, however, that & cast-expression is a pointer, not an address. ANSI C does not require that the value of a pointer (or the pointer cast to int) be the absolute address of the object pointed at although this is commonly the case. Furthermore, referencing may not have a unique definition on machines with a segmented address space. The use of MPI_Address to "reference" C variables guarantees portability to such machines as well. .SH ERRORS Almost all MPI routines return an error value; C routines as the value of the function and Fortran routines in the last argument. C++ functions do not return errors. If the default error handler is set to MPI::ERRORS_THROW_EXCEPTIONS, then on error the C++ exception mechanism will be used to throw an MPI::Exception object. .sp Before the error value is returned, the current MPI error handler is called. By default, this error handler aborts the MPI job, except for I/O function errors. The error handler may be changed with MPI_Comm_set_errhandler; the predefined error handler MPI_ERRORS_RETURN may be used to cause error values to be returned. Note that MPI does not guarantee that an MPI program can continue past an error. .SH SEE ALSO MPI_Get_address .br