A tiny question about memcpy

This is a discussion on A tiny question about memcpy within the C++ Programming forums, part of the General Programming Boards category; Hello, I am new to C++. I know the use of function memcpy(). but what is the difference between using ...

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    A tiny question about memcpy

    Hello, I am new to C++.
    I know the use of function memcpy().
    but what is the difference between using memcpy(&str1, &str2, sizeof(str2)) and str1 = str2 ?

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    memcpy will copy the contents of an address for n bytes. str1 = str2 will assign the address str2 to str1 (assuming they're pointers).

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    Originally posted by Enmeduranki
    memcpy will copy the contents of an address for n bytes. str1 = str2 will assign the address str2 to str1 (assuming they're pointers).
    is memcpy() slower if I want to copy a exact variable ?

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    >is memcpy() slower if I want to copy a exact variable ?

    You're not copying an exact variable by assigning one pointer to another. You're copying a pointer.

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    Originally posted by Enmeduranki
    >is memcpy() slower if I want to copy a exact variable ?

    You're not copying an exact variable by assigning one pointer to another. You're copying a pointer.
    how if I using * before a pointer ?

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    If you're only copying sizeof(one primitive) then yes.

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    Originally posted by Enmeduranki
    If you're only copying sizeof(one primitive) then yes.
    you mean memcpy() is slower ?

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    Almost definitely, but it'll be up to the implementation.

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    Thanks !

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