convert reference to pointer?

This is a discussion on convert reference to pointer? within the C++ Programming forums, part of the General Programming Boards category; Hi, I have a function that gives me a string reference: Code: int funcA (string &s) { ...} and within ...

  1. #1
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    convert reference to pointer?

    Hi,

    I have a function that gives me a string reference:
    Code:
    int funcA (string &s)
    { ...}
    and within there I need to call a function that takes a void pointer:
    Code:
    int funcB(void *v) { ...}
    is there any way to convert the string reference to a void pointer?

    basically I want to call something like this (pass in the address of s)
    Code:
     int result = funcB( &s );

  2. #2
    and the Hat of Guessing tabstop's Avatar
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    What does funcB expect about the void pointer it is given? If it just using it as memory, then just pass in the address. If it expects say a character string, then you'll have to turn your string into a char[] or similar.

  3. #3
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    hmm,... actually I didn't expect funcB( &s ) to work
    but I guess it does!

    I thought since s was already a reference, that taking the address of s would be some kind of a double pointer. But I guess I thought wrong

  4. #4
    Algorithm Dissector iMalc's Avatar
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    Think of it this way: Everything you do on a reference operates as if you performed it on the variable it is referencing - including taking the address of it.
    So whether s was a reference or not, you're taking the address of some string instance somewhere.
    My homepage
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  5. #5
    Cat without Hat CornedBee's Avatar
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    And very, very likely, there's nothing useful funcB can do with the address.
    All the buzzt!
    CornedBee

    "There is not now, nor has there ever been, nor will there ever be, any programming language in which it is the least bit difficult to write bad code."
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