help with memory size

This is a discussion on help with memory size within the C Programming forums, part of the General Programming Boards category; hey..i m having trouble with fixed-length format..suppose i wanna create a struct to store my variables n later on convert ...

  1. #1
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    help with memory size

    hey..i m having trouble with fixed-length format..suppose i wanna create a struct to store my variables n later on convert it into binary file format from raw text file like below :

    /* this only part of the source code. not a full program*/

    Code:
    struct test {
    
      char a[10];
      char b[10];
      char c[5];
      unsigned int d;
    
      };
    how do i made the int d occupy at most 1 byte to be stored in binary format (for eg.if int d is equal to 48 and it must stored in 48(in decimal)
    but it must no be stored as the string 48, that occupying 2 bytes. Can anyone give a tips??Thanks

  2. #2
    Tropical Coder Darryl's Avatar
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    If you are sure the integer is <= 255 you can cast it as an unsigned char, but if that's the case then why not just use unsigned char to begin with

  3. #3
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    yea..thanks for reply..but because i need to read in the file and store in struct and later on i will be able to write back to binary file format and if i using unsigned char will the output will be different from unsigned int??

  4. #4
    and the hat of wrongness Salem's Avatar
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    But if it's always <= 255, then just leave it as unsigned char.

    You can still do normal arithmetic on it if you want to.
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