confused abut pointers

This is a discussion on confused abut pointers within the C Programming forums, part of the General Programming Boards category; hi all, I've a truble with slimilar of this code.. Code: struct first *st; struct second *q; func(struct f *s, ...

  1. #1
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    confused abut pointers

    hi all,
    I've a truble with slimilar of this code..
    Code:
    struct first *st;
    struct second *q;
    func(struct f *s, struct s *ku){
    ......
    return func(s,ku);
    }
    errno=func(q,st); //warning: passing argument 2 of 'func' from incompatible pointer type
    I wrote two equal methog structs usage, but second take it's warning. Why it's happened?

  2. #2
    CSharpener vart's Avatar
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    because types of parameters are different in 2 calls
    The first 90% of a project takes 90% of the time,
    the last 10% takes the other 90% of the time.

  3. #3
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    Quote Originally Posted by vart View Post
    because types of parameters are different in 2 calls
    where? I'm not posted any syscalls, or what's calls?

  4. #4
    CSharpener vart's Avatar
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    s and q are of types struct f * and struct s * (parameters passed in the line return func(s,ku); )

    q and st are of types struct second * and struct first * (passed in the line errno=func(q,st); ) which is different from struct f * and struct s *
    The first 90% of a project takes 90% of the time,
    the last 10% takes the other 90% of the time.

  5. #5
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    possible I take a mistake in that sapmle. please, can you tell me it more clearly?
    there..

    Code:
    struct first *fir;
    struct second *sec;
    func(struct firs *fi, struct s *se){
    ......
    return func(fi,se); // return value from func which take pointer on struct firs  and s
    }
    errno=func(fir,sec); // take pointer on struct first  and second
    //warning: passing argument 2 of 'func' from incompatible pointer type

  6. #6
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    struct s != struct sec

    --
    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.

  7. #7
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    Quote Originally Posted by matsp View Post
    struct s != struct sec
    ok, what I should do so as to improve this?
    I want to input two structs into func.

  8. #8
    CSharpener vart's Avatar
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    Quote Originally Posted by quantt View Post
    ok, what I should do so as to improve this?
    I want to input two structs into func.
    there is nothing to improve. You should decide what type parameters of the function are and provide exactly that type of variables
    The first 90% of a project takes 90% of the time,
    the last 10% takes the other 90% of the time.

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