1MPI_Ssend_init(3) LAM/MPI MPI_Ssend_init(3)
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6 MPI_Ssend_init - Builds a handle for a synchronous send
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9 #include <mpi.h>
10 int MPI_Ssend_init(void *buf, int count, MPI_Datatype dtype,
11 int dest, int tag, MPI_Comm comm,
12 MPI_Request *req)
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15 buf - initial address of send buffer (choice)
16 count - number of elements sent (integer)
17 dtype - type of each element (handle)
18 dest - rank of destination (integer)
19 tag - message tag (integer)
20 comm - communicator (handle)
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24 req - communication request (handle)
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28 The communication initialized by this function will not be started
29 until req is given to MPI_Start or MPI_Startall .
30 The communication is then not guaranteed to progress or complete until
33 req has been given to one of the test or wait functions ( MPI_Test ,
34 MPI_Testall , MPI_Testany , MPI_Testsome , MPI_Wait , MPI_Waitall ,
35 MPI_Waitany , MPI_Waitsome ). The communication will not complete
36 until the destination rank starts to receive the message. Note that
37 this is different than saying that the message has been received by the
38 destination rank.
39 Once any of the test or wait functions indicate that the communication
42 has finished, the communication cycle can be started again with
43 MPI_Start or MPI_Startall .
44 However, once the communication has finished and it is no longer going
47 to be used, req should be freed with MPI_Request_free .
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52 All MPI routines in Fortran (except for MPI_WTIME and MPI_WTICK ) have
53 an additional argument ierr at the end of the argument list. ierr is
54 an integer and has the same meaning as the return value of the routine
55 in C. In Fortran, MPI routines are subroutines, and are invoked with
56 the call statement.
57 All MPI objects (e.g., MPI_Datatype , MPI_Comm ) are of type INTEGER in
59 Fortran.
60
63 If an error occurs in an MPI function, the current MPI error handler is
64 called to handle it. By default, this error handler aborts the MPI
65 job. The error handler may be changed with MPI_Errhandler_set ; the
66 predefined error handler MPI_ERRORS_RETURN may be used to cause error
67 values to be returned (in C and Fortran; this error handler is less
68 useful in with the C++ MPI bindings. The predefined error handler
69 MPI::ERRORS_THROW_EXCEPTIONS should be used in C++ if the error value
70 needs to be recovered). Note that MPI does not guarantee that an MPI
71 program can continue past an error.
72 All MPI routines (except MPI_Wtime and MPI_Wtick ) return an error
74 value; C routines as the value of the function and Fortran routines in
75 the last argument. The C++ bindings for MPI do not return error val‐
76 ues; instead, error values are communicated by throwing exceptions of
77 type MPI::Exception (but not by default). Exceptions are only thrown
78 if the error value is not MPI::SUCCESS .
79 Note that if the MPI::ERRORS_RETURN handler is set in C++, while MPI
82 functions will return upon an error, there will be no way to recover
83 what the actual error value was.
84 MPI_SUCCESS
85 - No error; MPI routine completed successfully.
86 MPI_ERR_COMM
87 - Invalid communicator. A common error is to use a null commu‐
88 nicator in a call (not even allowed in MPI_Comm_rank ).
89 MPI_ERR_COUNT
90 - Invalid count argument. Count arguments must be non-negative;
91 a count of zero is often valid.
92 MPI_ERR_TYPE
93 - Invalid datatype argument. May be an uncommitted MPI_Datatype
94 (see MPI_Type_commit ).
95 MPI_ERR_TAG
96 - Invalid tag argument. Tags must be non-negative; tags in a
97 receive ( MPI_Recv , MPI_Irecv , MPI_Sendrecv , etc.) may also
98 be MPI_ANY_TAG . The largest tag value is available through the
99 the attribute MPI_TAG_UB .
100 MPI_ERR_RANK
102 - Invalid source or destination rank. Ranks must be between
103 zero and the size of the communicator minus one; ranks in a
104 receive ( MPI_Recv , MPI_Irecv , MPI_Sendrecv , etc.) may also
105 be MPI_ANY_SOURCE .
106
110 MPI_Ssend, MPI_Start, MPI_Startall, MPI_Test, MPI_Testall, MPI_Testany,
111 MPI_Testsome, MPI_Wait, MPI_Waitall, MPI_Waitany, MPI_Waitsome
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115 For more information, please see the official MPI Forum web site, which
116 contains the text of both the MPI-1 and MPI-2 standards. These docu‐
117 ments contain detailed information about each MPI function (most of
118 which is not duplicated in these man pages).
119 http://www.mpi-forum.org/
121
125 The LAM Team would like the thank the MPICH Team for the handy program
126 to generate man pages ("doctext" from ftp://ftp.mcs.anl.gov/pub/sow‐
127 ing/sowing.tar.gz ), the initial formatting, and some initial text for
128 most of the MPI-1 man pages.
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131 ssendinit.c
132LAM/MPI 7.1.2 2/23/2006 MPI_Ssend_init(3)