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Subject: Re: [OMPI users] Problem with MPI_File_read() (2)
From: Jovana Knezevic (jovana.knezevic.83_at_[hidden])
Date: 2009-04-15 05:06:21


>
> In general, files written by MPI_File_write (and friends) are only
> guaranteed to be readable by MPI_File_read (and friends). So if you
> have an ASCII input file, or even a binary input file, you might need
> to read it in with traditional/unix file read functions and then write
> it out with MPI_File_write. Then your parallel application will be
> able to use the various MPI_File_* functions to read the file at run-
> time. Hence, there's no real generic <non-MPI-file> -> <MPI-file>
> convertor; you'll need to write your own that is specific to your data.
>
> Make sense?

Hello Jeff!

Thanks a lot!
Yes, sure, what you say makes sense. On the other hand, it seems I
will have to "traditionaly"-open the input file for n times - each one
for one process, since anyway all of my processes have to collect
their data from it (each parsing it from the beginning to the end),
don't you think so? I wanted to take an advantage of MPI to read (in
each process) the data from one file... Or have I misunderstood
something?