1MPI_Recv(3) LAM/MPI MPI_Recv(3)
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6 MPI_Recv - Basic receive
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9 #include <mpi.h>
10 int MPI_Recv(void *buf, int count, MPI_Datatype dtype,
11 int src, int tag, MPI_Comm comm, MPI_Status *stat)
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14 count - maximum number of elements in receive buffer (integer)
15 dtype - datatype of each receive buffer element (handle)
16 src - rank of source (integer)
17 tag - message tag (integer)
18 comm - communicator (handle)
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22 buf - initial address of receive buffer (choice)
23 stat - status object (Status), which can be the MPI constant MPI_STA‐
24 TUS_IGNORE if the return status is not desired
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28 The count argument indicates the maximum length of a message; the
29 actual number can be determined with MPI_Get_count .
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34 All MPI routines in Fortran (except for MPI_WTIME and MPI_WTICK ) have
35 an additional argument ierr at the end of the argument list. ierr is
36 an integer and has the same meaning as the return value of the routine
37 in C. In Fortran, MPI routines are subroutines, and are invoked with
38 the call statement.
39 All MPI objects (e.g., MPI_Datatype , MPI_Comm ) are of type INTEGER in
41 Fortran.
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45 If an error occurs in an MPI function, the current MPI error handler is
46 called to handle it. By default, this error handler aborts the MPI
47 job. The error handler may be changed with MPI_Errhandler_set ; the
48 predefined error handler MPI_ERRORS_RETURN may be used to cause error
49 values to be returned (in C and Fortran; this error handler is less
50 useful in with the C++ MPI bindings. The predefined error handler
51 MPI::ERRORS_THROW_EXCEPTIONS should be used in C++ if the error value
52 needs to be recovered). Note that MPI does not guarantee that an MPI
53 program can continue past an error.
54 All MPI routines (except MPI_Wtime and MPI_Wtick ) return an error
56 value; C routines as the value of the function and Fortran routines in
57 the last argument. The C++ bindings for MPI do not return error val‐
58 ues; instead, error values are communicated by throwing exceptions of
59 type MPI::Exception (but not by default). Exceptions are only thrown
60 if the error value is not MPI::SUCCESS .
61 Note that if the MPI::ERRORS_RETURN handler is set in C++, while MPI
64 functions will return upon an error, there will be no way to recover
65 what the actual error value was.
66 MPI_SUCCESS
67 - No error; MPI routine completed successfully.
68 MPI_ERR_COMM
69 - Invalid communicator. A common error is to use a null commu‐
70 nicator in a call (not even allowed in MPI_Comm_rank ).
71 MPI_ERR_TYPE
72 - Invalid datatype argument. May be an uncommitted MPI_Datatype
73 (see MPI_Type_commit ).
74 MPI_ERR_COUNT
75 - Invalid count argument. Count arguments must be non-negative;
76 a count of zero is often valid.
77 MPI_ERR_TAG
78 - Invalid tag argument. Tags must be non-negative; tags in a
79 receive ( MPI_Recv , MPI_Irecv , MPI_Sendrecv , etc.) may also
80 be MPI_ANY_TAG . The largest tag value is available through the
81 the attribute MPI_TAG_UB .
82 MPI_ERR_RANK
84 - Invalid source or destination rank. Ranks must be between
85 zero and the size of the communicator minus one; ranks in a
86 receive ( MPI_Recv , MPI_Irecv , MPI_Sendrecv , etc.) may also
87 be MPI_ANY_SOURCE .
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92 For more information, please see the official MPI Forum web site, which
93 contains the text of both the MPI-1 and MPI-2 standards. These docu‐
94 ments contain detailed information about each MPI function (most of
95 which is not duplicated in these man pages).
96 http://www.mpi-forum.org/
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102 The LAM Team would like the thank the MPICH Team for the handy program
103 to generate man pages ("doctext" from ftp://ftp.mcs.anl.gov/pub/sow‐
104 ing/sowing.tar.gz ), the initial formatting, and some initial text for
105 most of the MPI-1 man pages.
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108 recv.c
109LAM/MPI 7.1.2 2/23/2006 MPI_Recv(3)