Strange EOF happenings

This is a discussion on Strange EOF happenings within the C Programming forums, part of the General Programming Boards category; For some reason, whenever the program reads 1A in hex, 26 in dec it is reading it as EOF. I ...

  1. #1
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    Strange EOF happenings

    For some reason, whenever the program reads 1A in hex, 26 in dec it is reading it as EOF. I have it print out the character and, sure enough, it prints -1. I don't get it. Other programs are detecting EOF just fine. Here's the culprit code:
    Code:
    new_byte = fgetc(_source);
       while(new_byte != EOF){
          decompress(new_byte, bit);
          for(i=0; i < (8/bit); i++){
             fputc(_new_pixels[i], _dest);
          }
          printf("%d: ", j);
          j++;
          new_byte = fgetc(_source);
          printf("%d\n", new_byte);
       }
    That is supposed to loop through over 8000 times, but it gets to byte number 206 and hit EOF. Here's the end of the output:

    Code:
    200: 0
    201: 0
    202: 15
    203: 255
    204: 139
    205: 47
    206: -1
    Byte number 206 is 26, not -1

    I changed byte 206 to 27, then it stopped on the next 26 later in the file.

    Any ideas?
    Thanks
    Last edited by fatinez; 09-23-2003 at 09:43 PM.

  2. #2
    Just Lurking Dave_Sinkula's Avatar
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    Is new_byte an int like it should be?
    7. It is easier to write an incorrect program than understand a correct one.
    40. There are two ways to write error-free programs; only the third one works.*

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    Yes sir.

  4. #4
    Just Lurking Dave_Sinkula's Avatar
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    Would something like this produce any clues?
    Code:
       new_byte = fgetc(_source);
       while ( new_byte != EOF ) {
    /*
          decompress(new_byte, bit);
          for(i=0; i < (8/bit); i++){
             fputc(_new_pixels[i], _dest);
          }
    */
          printf("%d: ", j);
          j++;
          new_byte = fgetc(_source);
          printf("%d\n", new_byte);
       }
       if(ferror(_source))
       {
          perror("_source");
       }
       if(feof(_source))
       {
          puts("Yup. EOF");
       }
    7. It is easier to write an incorrect program than understand a correct one.
    40. There are two ways to write error-free programs; only the third one works.*

  5. #5
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    Code:
    200: 0
    201: 0
    202: 15
    203: 255
    204: 139
    205: 47
    206: -1
    Yup. EOF
    That's interesting. By the way, the source file is 8196 bytes.

    It only does that in Windows. I compile and run it on UNIX over ssh and it works fine. But it is going to be graded on a Windows machine. Maybe I'll just do it in UNIX and make a note of the problem.

    Here's the end of execution in UNIX:
    Code:
    8192: 0
    8193: 0
    8194: 0
    8195: 0
    8196: 0
    8197: -1
    Yup. EOF
    Last edited by fatinez; 09-23-2003 at 09:36 PM.

  6. #6
    Just Lurking Dave_Sinkula's Avatar
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    I don't seem to be all that helpful here. One more try: is _source opened in binary mode?
    7. It is easier to write an incorrect program than understand a correct one.
    40. There are two ways to write error-free programs; only the third one works.*

  7. #7
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    HOLY CRAP!! That worked.

    Thanks a million Dave.

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