Thread: Need help writing to file

  1. #1
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    Need help writing to file

    I need help writing to a file. I can't get it to work but its not giving any errors.
    Code:
    #define OUTPUT "output.txt"
    ...
    out = fopen(OUTPUT, "w");
    if(!out) fatal("Could not open %s for writing\n", OUTPUT);
    fprintf(out, "Got Here");
    There is no compile error, there is a segmentation fault, but that occurs later in the code. I have print statements that get printed before the segmentation fault. After i run the code, the message "Got Here" does not get printed to output.txt. I also open another stream for writing later in the code, but it is after all this happens, and it does not work either. Any help is appreciated.

  2. #2
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    In all likelihood it's the segfault causing the problem.... If your files are still open when it occurs the data will be in memory buffers that probably don't get written to disk. Try closing the file immediately after your fprintf() call and see what happens.

  3. #3
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    Quote Originally Posted by dford425 View Post
    There is no compile error, there is a segmentation fault, but that occurs later in the code.
    Which means it will be hard to say what is causing it based on what you have posted.

    Quote Originally Posted by CommonTater View Post
    In all likelihood it's the segfault causing the problem.... If your files are still open when it occurs the data will be in memory buffers that probably don't get written to disk. Try closing the file immediately after your fprintf() call and see what happens.
    I agree, fflush() should work as well.

  4. #4
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    Thanks for the quick replys, fflush() worked.

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