Thread: Overriding C run-time functions

  1. #1
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    Question Overriding C run-time functions

    Hi, does anyone know how to override the C run-time functions. I need to write my own malloc() function with the same function signature as Microsoft's C run-time malloc(). Any suggestion/help? When I link my program I get error message indicating a duplicate function.
    Last edited by rassul; 09-12-2004 at 11:03 PM.

  2. #2
    Gawking at stupidity
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    #define malloc(x) my_malloc(x)

    Then write your malloc() implementation as my_malloc().
    If you understand what you're doing, you're not learning anything.

  3. #3
    Obsessed with C chrismiceli's Avatar
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    I don't know what compiler you are using, but if you are writing your own malloc(), I am guessing you aren't going for portability. Looking at my stdlib.h, gcc, I found this macro: __need_malloc_and_calloc. Might want to mess with that and see what happens.
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  4. #4
    Registered User linuxdude's Avatar
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    if you are lucky and don't use any function from stdlib.h then just don't include it and then define malloc yourself.

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    Thank you all for your help.

  6. #6
    Banned master5001's Avatar
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    Why not just write your own version of malloc() and give it another name? I think thats ultimately the best way of doing this.

  7. #7
    and the hat of int overfl Salem's Avatar
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    If you're using Linux (or at least GNU LD), then
    http://www.gnu.org/software/binutils...l_mono/ld.html
    and look at
    --wrap symbol
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.

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