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<div style="direction: ltr;font-family: Tahoma;color: #000000;font-size: 10pt;">Hello all,
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<div>I am trying to use two raspberry-pi to sample and then process some data. The first process samples while the second processes and vice versa. To do this I use gpio and also mpich-3.0.4 with the process manager smpd. I have successfully run cpi on both
machines (from the master machine). I have also managed to run a similar program but without the MPI, this involved compiling with gcc and when running putting sudo in front of the binary file.</div>
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<div>When I combine these two processes I get various error messages. </div>
<div>For input:</div>
<div><span style="font-size: 10pt;">mpiexec -phrase cat -machinefile machinefile -n 2 </span><span style="font-size: 10pt;">~/main </span></div>
<div><span style="font-size: 10pt;">the error is:</span></div>
<div><span style="font-size: 10pt;">Can't open /dev/mem</span></div>
<div><span style="font-size: 10pt;">Did you forget to use 'sudo .. ?'</span></div>
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<div>For input:</div>
<div><span style="font-size: 10pt;">sudo mpiexec -phrase cat -machinefile machinefile -n 2 </span><span style="font-size: 10pt;">~/main </span></div>
<div><span style="font-size: 10pt;">the error is:</span></div>
<div>sudo: mpiexec: Command not found</div>
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<div>I therefore put mpiexec into /usr/bin</div>
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<div>now f<span style="font-size: 10pt;">or input:</span></div>
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<div><span style="font-size: 10pt;">sudo mpiexec -phrase cat -machinefile machinefile -n 2 </span><span style="font-size: 10pt;">~/main </span></div>
<div><span style="font-size: 10pt;">the error is:</span></div>
<div><span style="font-size: 10pt;">Can't open /dev/mem</span></div>
<div><span style="font-size: 10pt;">Did you forget to use 'sudo .. ?'</span></div>
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<div><span style="font-size: 10pt;">Does anyone know how I can work around this?</span></div>
<div><span style="font-size: 10pt;">Thanks,</span></div>
<div><span style="font-size: 10pt;">Eibhlin </span></div>
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