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I am working on a test application where I am reading/writing files for processing. On the
simulator everything is working perfect, but when running on emulator/board, the fopen()
returns null. It is happening quite frequently, but not all the time. I also tried with both
relative (w.r.t executable file) and absolute files paths. The part of the code is here; can
some one help what is going wrong.

 char rOutfile[200]="../testvecs/op/r_out.out";
 char bOutfile[200]="../testvecs/op/b_out.yuv";

    fpr = fopen(rOutfile, "wb");
    if (!fpr) {
        /* control almost always comes here */
        return;
    }
    fpb = fopen(bOutfile, "wb");
    if ( !fpb) {
        /* control almost always comes here */
        fclose(fpr);
        return;
    }

------------------------------------

OMAP35x EVM jump-starts low-power apps
------------------------------------
The modular and extensible OMAP35x Evaluation Module (EVM) enables developers to start building
applications based on the OMAP35x architecture:http://www.DSPRelated.com/omap35x

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Venki-

> I am working on a test application where I am reading/writing files
> for processing. On the simulator everything is working perfect, but
> when running on emulator/board, the fopen() returns null. It is
> happening quite frequently, but not all the time. I also tried with
> both relative (w.r.t executable file) and absolute files paths. The
> part of the code is here; can some one help what is going wrong.
> 
>  char rOutfile[200]="../testvecs/op/r_out.out";
>  char bOutfile[200]="../testvecs/op/b_out.yuv";
> 
>     fpr = fopen(rOutfile, "wb");
>     if (!fpr) {
>         /* control almost always comes here */
>         return;
>     }
>     fpb = fopen(bOutfile, "wb");
>     if ( !fpb) {
>         /* control almost always comes here */
>         fclose(fpr);
>         return;
>     }

I'm not sure of the reason for the NULL return, but I might make a couple of
comments:

1) If you are running the above code during real-time processing -- i.e. when other
code/interrupts/DMA is making onchip memory bus and CPU demands -- then you are
likely to see problems.  CCS file I/O uses the JTAG emulator connection, which is
typically very slow, causing code such as the above to take a long time and in turn
affect timing and performance.

2) Normally CCS file I/O should only be used "when nothing else is going on", for
example at the beginning of main() to initialize some arrays, or at a known "stop or
pause point" for debug purposes.

You could try some things to improve efficiency.  You could open the files in main.c
before real-time code starts, and save the file handles.  Then you could save the
data in memory after each frame, and write to file later, maybe after N number of
frames were processed.

-Jeff

------------------------------------

OMAP35x EVM jump-starts low-power apps
------------------------------------
The modular and extensible OMAP35x Evaluation Module (EVM) enables developers to start building
applications based on the OMAP35x architecture:http://www.DSPRelated.com/omap35x

(You need to be a member of code-comp -- send a blank email to code-comp-subscribe@yahoogroups.com )