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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Does MPI_COMM_WORLD exist in any sense before MPI_Init is called? In particular, does this code violate the standard?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">InitializeMyApp(MPI_Comm comm, int argc, char **argv)<o:p></o:p></p>
<p class="MsoNormal">{<o:p></o:p></p>
<p class="MsoNormal"> int initialized;<o:p></o:p></p>
<p class="MsoNormal"> MPI_Initialized(&initialized);<o:p></o:p></p>
<p class="MsoNormal"> if (!initialized) MPI_Init(&argc, &argv);<o:p></o:p></p>
<p class="MsoNormal"> /* call some function that uses comm */<o:p></o:p></p>
<p class="MsoNormal">}<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">int main(int argc, char **argv)<o:p></o:p></p>
<p class="MsoNormal">{<o:p></o:p></p>
<p class="MsoNormal"> MPI_Comm comm = MPI_COMM_WORLD;<o:p></o:p></p>
<p class="MsoNormal"> InitializeMyApp(comm, argc, argv);<o:p></o:p></p>
<p class="MsoNormal"> :<o:p></o:p></p>
<p class="MsoNormal">}<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">My instinct is that this is wrong, but I would like to be sure before I complain about it. It appears to work with some existing implementations, but it looks sketchy to me.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Bruce<o:p></o:p></p>
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