Thanks Jeff, you are right, I'm trying POSIX file writing functions now.
Jeff Squyres wrote:
> IIRC, the MPI standard says that files created by MPI I/O should only
> be read by MPI I/O. I have actually not used ROMIO (the package that
> is included in LAM/MPI to effect the MPI-2 I/O functionality), but I'm
> pretty sure that it takes advantage of this rule.
>
> Hence, if you want to read the file back out, you should be using an
> MPI application to do so.
>
> Keep in mind that the MPI_File_* functions are really for parallel
> reading and writing of files. If all you want to do is read and write
> some simple text files (in serial), you might be better served with
> normal POSIX file writing functions in a single MPI process (e.g.,
> open, fopen, write, fwrite, etc.). I.e., it's no uncommon, depending
> on your specific application's requirements, to have something like:
>
> if (i_am_the_master) {
> /* ...receive results from all other processes... */
> fp = fopen("results.dat", "w");
> fwrite(fp, ...);
> fclose(fp);
> }
>
> (sample only; always check your return values, etc.)
>
>
> On Apr 12, 2005, at 5:09 PM, Guoli Wang wrote:
>
>> Dear all,
>>
>> I have some troubles on reading output file from MPI running. I use
>> following code line to write a string onto output file on eac node:
>>
>> MPI_File_write(OUT, &result, stringlength, MPI_CHAR, &status);
>>
>> where result is a string. But when I want read the output, I could
>> not find the easy way to convert the output file into ascii file. I
>> tried "od -c" but it split all the words into characters, I tried "od
>> -s", it only give part of the whole string. Any other way to do that?
>>
>>
>> Thanks,
>>
>> Guoli
>>
>> --
>> Guoli Wang
>> Bioinformatics
>> Fox Chase Cancer Center
>> 7701 Burlhome Avenue
>> Philadelphia, PA 19111
>> Phone: (215) 728 5661
>> Email: GL_Wang_at_[hidden]
>>
>> _______________________________________________
>> This list is archived at http://www.lam-mpi.org/MailArchives/lam/
>>
>
--
Guoli Wang
Bioinformatics
Fox Chase Cancer Center
7701 Burlhome Avenue
Philadelphia, PA 19111
Phone: (215) 728 5661
Email: GL_Wang_at_[hidden]
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