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MPI_Pcontrol(3) man page (version 1.3.4)

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NAME

       MPI_Pcontrol - Controls profiling.

SYNTAX


C Syntax

       #include <mpi.h>
       int MPI_Pcontrol(const int level, ... )

Fortran Syntax

       INCLUDE 'mpif.h'
       MPI_PCONTROL(LEVEL)
            INTEGER   LEVEL, ...

C++ Syntax

       #include <mpi.h>
       void Pcontrol(const int level, ...)

INPUT PARAMETER

       level     Profiling level.

DESCRIPTION

       MPI  libraries  themselves  make  no  use  of this routine; they simply
       return immediately to the user code. However the presence of  calls  to
       this  routine allows a profiling package to be explicitly called by the
       user.

       Since MPI has no control of the implementation of the  profiling  code,
       we  are unable to specify precisely the semantics that will be provided
       by calls to MPI_Pcontrol. This vagueness extends to the number of argu-
       ments to the function, and their datatypes.

       However to provide some level of portability of user codes to different
       profiling libraries, we request the following meanings for certain val-
       ues of level:

         o    level==0  Profiling is disabled.

         o    level==1  Profiling  is  enabled  at  a  normal default level of
              detail.

         o    level==2  Profile buffers are flushed. (This may be a  no-op  in
              some profilers).

         o    All  other  values of level have profile library-defined effects
              and additional arguments.

       We also request that the default state after MPI_Init has  been  called
       is for profiling to be enabled at the normal default level (i.e., as if
       MPI_Pcontrol had just been called with the  argument  1).  This  allows
       users  to link with a profiling library and obtain profile output with-
       out having to modify their source code at all.

       interpretation of level and any other arguments is left to the  profil-
       ing library.

       This  function does not return an error value. Consequently, the result
       of calling it before MPI_Init or after MPI_Finalize is undefined.

1.3.4                            Nov 11, 2009                  MPI_Pcontrol(3)

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