A doubt regarding FILE * pointer

This is a discussion on A doubt regarding FILE * pointer within the C Programming forums, part of the General Programming Boards category; Hello everyone, While learning C File I/O I tried the following code : Code: #include<stdio.h> int main() { FILE *fp; ...

  1. #1
    Registered User
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    May 2008
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    A doubt regarding FILE * pointer

    Hello everyone,

    While learning C File I/O I tried the following code :

    Code:
    #include<stdio.h>
    
    int main()
    {
            FILE *fp;
            fp=fopen("source.txt","rb");
            printf("fp = %p\n",fp++);
            printf("fp = %p\n",fp);
            return 0;
    }
    #gcc prg.c
    #./a.out
    Gives the following output :

    fp = 0x8e2a008
    fp = 0x8e2a09c

    On incrementing fp and printing the values there is a difference of 0X94 or 148. How does the difference come to 148?

    Thank you.

  2. #2
    Registered User
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    6,657
    The size of a FILE type is 148 for gcc and its library on your system.

  3. #3
    Registered User
    Join Date
    May 2008
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    31
    Thanks for the answer I tried

    Code:
    printf("%d\n",sizeof(FILE));
    and got 148.

  4. #4
    Kernel hacker
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    Farncombe, Surrey, England
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    And it's pretty pointless.

    --
    Mats
    Compilers can produce warnings - make the compiler programmers happy: Use them!
    Please don't PM me for help - and no, I don't do help over instant messengers.

  5. #5
    Registered User
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    May 2008
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    i am still in the process of learning C, so just tried that. I know its pointless.

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