Thread: Dynamically allocated memory question

  1. #1
    Registered User
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    Dynamically allocated memory question

    Consider this:
    Code:
    int i;
    char *v[MAXELEMENTS];
    
    for (i = 0; i < MAXELEMENTS; i++) {
        if ((v[i] = malloc(blablabla)) == NULL) {
            printf("error\n");
            while (--i >= 0)
                free(v[i]);
            break;
        }
    
        do something with v[i]...
    }
    Is the part in red necessary if I exit the program right after displaying the error message?

  2. #2
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    If it exits then i guess it should be fine, cause after program exits, the memory used by it , is anyway returned back to the OS. But i don't think you can always count on that.

    Nevertheless, its always in your best interest to free what you allocate.

  3. #3
    Confused Magos's Avatar
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    Most (all?) OS's should return the memory when a program exits, but if you sometime somewhere somehow program for a small embedded system this might not be the case...
    MagosX.com

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  4. #4
    Rabble Rouser Slacker's Avatar
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    >Is the part in red necessary if I exit the program right after displaying the error message?
    Necessary? Nope. But it's definitely a good idea, especially since nobody tries to write bad code, and good code usually gets reused. So what could terminate immediately now would probably become a library later and then you'd have a nice little memory leak.

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