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Linked list in c add to front

So I'm really confused. I am trying to write a c method that allows me to add a new "node" to the top of a linked list. I have done this before in C ++ and no problem. I am upset because after writing the code I was sure that I was right, I went and looked around, and basically wherever I find it says that I am doing the same thing as everything that I am ready ... I I will give the code and step-by-step addresses and values ​​of variables. Here is the code:

Real function:

void addToBeginning(int value, struct node* root){
    struct node* newNode;
    newNode = malloc( sizeof(struct node));
    newNode->value = value;
    newNode->next = root;
    root = newNode;
}

But here is the full code. I removed some things to make it more concise (things that are not needed to answer this question, for example getLength (...) and addToPos (...))

#include <stdio.h>
#include <stdlib.h>

struct node {
    int value;
    struct node* next;
};

void printLinkedList(struct node* root);

void addToEnd(int value, struct node* root);

void addToBeginning(int value, struct node* root);

void addToPos(int pos, int value, struct node* root);

int getLength(struct node* root);


int main(){        
    /**
     TESTING addToBeginning (I know addToEnd works)
     **/

    struct node *root2;
    root2 = malloc( sizeof(struct node));
    root2->value = 4;
    root2->next = NULL;

    /*
     root2 = 4 -> 0 -> 0 -> 0 -> 0 -> 0 -> 0
     */
    i = 0;
    while (i < 5){
        addToEnd(0,root2);
        i++;
    }

    printLinkedList(root2);
    //printf("Length : %d\n",getLength(root2));

    /*
     expected root2 = 2 -> 4 -> 0 -> 0 -> 0 -> 0 -> 0
     */
    addToBeginning(2, root2);
    printLinkedList(root2);
    /*
     obtained root2 = 4 -> 0 -> 0 -> 0 -> 0 -> 0 -> 0
     */
    //printf("Length : %d\n",getLength(root2));

    return(0);
}

void printLinkedList(struct node* root){
    while(root != NULL){
        if (root->next != NULL){
            printf("%d, ",root->value);
            root=root->next;
        } else {
            printf("%d\n",root->value);
            root=root->next;
        }
    }

}

void addToEnd(int value, struct node* root){
    /*
     Set up new node
     */
    struct node* newNode = malloc( sizeof(struct node));
    newNode->value = value;
    newNode->next = NULL;

    /*
     Check if empty linked list first
     */
    if (root->next == NULL){
        root->next = newNode;
    } else {
        /*
         Find the last node
         */
        struct node* current = root;
        while(current->next != NULL){
            current = current->next;
        }
        current->next = newNode;
    }
}

void addToBeginning(int value, struct node* root){
    struct node* newNode;
    newNode = malloc( sizeof(struct node));
    newNode->value = value;
    newNode->next = root;
    root = newNode;
}

What is confusing, I feel like there is a problem with an alias on

newNode->next = root;
root = newNode;

... , : ... addToBeginning(int value, struct node* root){...} :

:

struct node* newNode;
newNode = malloc( sizeof(struct node));

root newNode:

root = 0x0000000100103c60
root->next = 0x0000000100103c70
root->value = 4
newNode = 0x0000000100103cc0
newNode->next = NULL
newNode->value = 0

:

newNode->value = value;

root newNode:

root = 0x0000000100103c60
root->next = 0x0000000100103c70
root->value = 4
newNode = 0x0000000100103cc0
newNode->next = NULL
newNode->value = 2

:

newNode->next = root;

root newNode:

root = 0x0000000100103c60
root->next = 0x0000000100103c70
root->value = 4
newNode = 0x0000000100103cc0
newNode->next = 0x0000000100103c60
newNode->value = 2

:

root = newNode;

root newNode:

root = 0x0000000100103cc0
root->next = 0x0000000100103c60
root->value = 2
newNode = 0x0000000100103cc0
newNode->next = 0x0000000100103c60
newNode->value = 2

, , *root , , 0x0000000100103c60, , , .

+4
2

void addToBeginning(int value, struct node* root){
    struct node* newNode;
    (...)
    root = newNode;
}

struct node *root2;
addToBeginning(2, root2);

. , , . .

:

void addToBeginning(int value, struct node **root){
    struct node* newNode;
    (...)
    *root = newNode;
}

struct node *root2;
addToBeginning(2, &root2);

. , ? , , , . , , ( ), node root2 *root2 = x node root2->member = y. , ( - [, ]], , ).

. , , .

+3

void addToBeginning(int value, struct node** root)

2 * root

root .

+1

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