Thread: Pointers and malloc

  1. #1

    Pointers and malloc

    Hi, I just have one quick question.
    I am doing something like this:

    char *buf = malloc(10);
    int file_descriptor = ... // just some file descriptor to read from

    read(file_descriptor, buf, 9);

    buf += 5;



    Now the question is, when I call free(buf), does it free up all 10 bytes of memory that were allocated? Or only the 5 bytes following the current address that buf is pointing to?


  2. #2
    I'm pretty sure that it will free 10 bytes but will free them starting at the point 5 from where you allocated them which could be very bad. But someone should probly confirm that

  3. #3
    Registered User biosx's Avatar
    Join Date
    Aug 2001
    It will free any memory allocated with it, so all 10 bytes.

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