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<meta http-equiv="Content-Type" content="text/html; charset=Windows-1252"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">Thanks. Yes, I believe this is a bug. The implementation of MPI_Info_get in MPICH passes valuelen to the internal copy routine, yet it is clear that the definition in the standard for MPI_Info_get, it should pass valuelen+1 (it should also check for the error return code from the internal routine and return a value MPI error code if the buffer is too small.<div><br></div><div>Bill</div><div><br><div><div>On Feb 1, 2015, at 12:13 AM, Hajime Fujita <<a href="mailto:hfujita@uchicago.edu">hfujita@uchicago.edu</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">
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<div class="PlainText">Hello,<br>
<br>
I came across some question about a behavior of MPI_Info_get in MPICH.<br>
<br>
If I knew the size of the value, what should I pass to MPI_Info_get as `valuelen`?<br>
Suppose I have 3-byte value in the info object, and I allocate 4-byte buffer including a space for null-termination. Then I think I should specify 3 as valuelen to retrieve the whole value, as the MPI-3 specifications says<br>
"In C, valuelen should be one less than the amount of allocated space to allow for the null terminator.<br>
<br>
However, when I run the attached program in MPICH 3.1.1, I get:<br>
$ ./test<br>
key found: vaule=va # The last character l is missing<br>
<br>
If I specify `sizeof(buff)` as valuelen, it shows val correctly.<br>
<br>
So apparently MPICH thinks valuelen includes null terminator.<br>
Am I missing anything, or any misunderstanding here?<br>
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<br>
Thank you in advance,<br>
Hajime<br>
<br>
--<br>
Hajime Fujita<br>
Postdoctoral Scholar, Large-Scale Systems Group<br>
Department of Computer Science, The University of Chicago<br>
<a href="http://www.cs.uchicago.edu/people/hfujita">http://www.cs.uchicago.edu/people/hfujita</a></div>
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<span><test.c></span></blockquote></div><br></div></body></html>