How to allocate memory dynamically for a struct

Asked Dec 04 '17 at 10:18

Active Dec 04 '17 at 10:27

Viewed 54 times

I have a struct which has an array of another struct inside its.

typedef struct info_single {
    pid_t pidx;
    int type;
} info_single;

struct shared_info {
    long indexx;
    struct info_single single_info[];
};

The size of the array is given by the user. How do I allocate the memory through a malloc? This is my solution but i don't know if it is correct

struct shared_info * data;
data = malloc(sizeof(*data)+n*sizeof(info_single));

edited Dec 04 '17 at 10:27

asked Dec 04 '17 at 10:18

What have you tried? How that failed? – Sourav Ghosh Dec 04 '17 at 10:20
A two-step allocation? the first one for `shared_info`, the second for the desired number of `info_single`s. – JFMR Dec 04 '17 at 10:21
1

_Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer. Avoid asking multiple distinct questions at once. See the How to Ask page for help clarifying this question.._ – Sourav Ghosh Dec 04 '17 at 10:22
I edited the question – Dec 04 '17 at 10:28
This is correct for me, but maybe use FMA for a beginner is a little hard... you could do the following too `data = malloc(sizeof *data + sizeof data->single_info * n);` – Stargateur Dec 04 '17 at 10:29
In this way can i do something like: data->single_info[0].type = 1 ? – Dec 04 '17 at 10:32
@JimBelushi2 yes. – Antti Haapala -- Слава Україні Dec 04 '17 at 10:33
The question is now good, but it is still a duplicate. Upvoted – Antti Haapala -- Слава Україні Dec 04 '17 at 10:34

How to allocate memory dynamically for a struct

0 Answers0