[97] | 1 | .\"Copyright 2006-2008 Sun Microsystems, Inc. |
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| 2 | .\" Copyright (c) 1996 Thinking Machines Corporation |
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| 3 | .TH MPI_Alloc_mem 3 "Dec 08, 2009" "1.4" "Open MPI" |
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| 4 | .SH NAME |
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| 5 | \fBMPI_Alloc_mem \fP \- Allocates a specified memory segment. |
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| 6 | |
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| 7 | .SH SYNTAX |
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| 8 | .ft R |
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| 9 | .SH C Syntax |
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| 10 | .nf |
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| 11 | #include <mpi.h> |
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| 12 | int MPI_Alloc_mem(MPI_Aint \fIsize\fP, MPI_Info \fIinfo\fP, void *\fIbaseptr\fP) |
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| 13 | |
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| 14 | .SH Fortran Syntax (see FORTRAN NOTES) |
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| 15 | .nf |
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| 16 | INCLUDE 'mpif.h' |
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| 17 | MPI_ALLOC_MEM(\fISIZE, INFO, BASEPTR, IERROR\fP) |
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| 18 | INTEGER \fIINFO, IERROR\fP |
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| 19 | INTEGER(KIND=MPI_ADDRESS_KIND) \fISIZE, BASEPTR\fP |
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| 20 | |
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| 21 | .SH C++ Syntax |
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| 22 | .nf |
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| 23 | #include <mpi.h> |
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| 24 | void* MPI::Alloc_mem(MPI::Aint \fIsize\fP, const MPI::Info& \fIinfo\fP) |
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| 25 | |
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| 26 | .SH INPUT PARAMETERS |
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| 27 | .ft R |
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| 28 | .TP 1i |
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| 29 | size |
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| 30 | Size of memory segment in bytes (nonnegative integer). |
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| 31 | .ft R |
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| 32 | .TP 1i |
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| 33 | info |
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| 34 | Info argument (handle). |
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| 35 | |
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| 36 | .SH OUTPUT PARAMETERS |
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| 37 | .ft R |
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| 38 | .TP 1i |
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| 39 | baseptr |
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| 40 | Pointer to beginning of memory segment allocated. |
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| 41 | .TP 1i |
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| 42 | IERROR |
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| 43 | Fortran only: Error status (integer). |
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| 44 | |
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| 45 | .SH DESCRIPTION |
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| 46 | .ft R |
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| 47 | MPI_Alloc_mem allocates \fIsize\fP bytes of memory. The starting address |
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| 48 | of this memory is returned in the variable \fIbase\fP. |
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| 49 | .sp |
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| 50 | |
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| 51 | .SH FORTRAN NOTES |
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| 52 | .ft R |
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| 53 | There is no portable FORTRAN 77 syntax for using MPI_Alloc_mem. |
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| 54 | There is no portable Fortran syntax for using pointers returned |
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| 55 | from MPI_Alloc_mem. However, MPI_Alloc_mem can be used with Sun |
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| 56 | Fortran compilers. |
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| 57 | .sp |
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| 58 | From FORTRAN 77, you can use the following non-standard |
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| 59 | declarations for the SIZE and BASEPTR arguments: |
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| 60 | .nf |
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| 61 | INCLUDE "mpif.h" |
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| 62 | INTEGER*MPI_ADDRESS_KIND SIZE, BASEPTR |
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| 63 | .fi |
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| 64 | .sp |
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| 65 | From either FORTRAN 77 or Fortran 90, you can use "Cray pointers" |
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| 66 | for the BASEPTR argument. Cray pointers are described further in |
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| 67 | the Fortran User's Guide and are supported by many Fortran compilers. |
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| 68 | For example, |
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| 69 | .sp |
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| 70 | .nf |
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| 71 | INCLUDE "mpif.h" |
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| 72 | REAL*4 A(100,100) |
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| 73 | POINTER (BASEPTR, A) |
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| 74 | INTEGER*MPI_ADDRESS_KIND SIZE |
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| 75 | |
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| 76 | SIZE = 4 * 100 * 100 |
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| 77 | CALL MPI_ALLOC_MEM(SIZE,MPI_INFO_NULL,BASEPTR,IERR) |
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| 78 | |
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| 79 | ! use A |
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| 80 | |
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| 81 | CALL MPI_FREE_MEM(A, IERR) |
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| 82 | .fi |
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| 83 | |
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| 84 | .SH ERRORS |
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| 85 | 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. |
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| 86 | .sp |
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| 87 | Before the error value is returned, the current MPI error handler is |
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| 88 | called. By default, this error handler aborts the MPI job, except for I/O function errors. The error handler |
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| 89 | 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. |
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| 90 | |
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| 91 | .SH SEE ALSO |
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| 92 | .ft R |
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| 93 | .sp |
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| 94 | MPI_Free_mem |
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