Unwanted pointers modification - c

Question

Situation: I'm currently working with chained lists and I am adding new elements through a function called inputRegistering(). I am positive that at the end of this function, an element have been added to the correct place.
Issue1: The added element modifies all the other to take its value.
Issue2: When exiting the function, and calling the inputReadingAll() function (which displays the list in its entirety), the elements are now all "empty", or replaced with gibberish (as can do the pointers).
Test1: I have tested to do a manual adding in the main() function and it seems everything worked fine. I can't understand what is the fundamental difference with my code though...
Code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define MAXLEN 256
typedef struct
{
struct elt *first;
struct elt *last;
} Tfile;
typedef struct elt
{
char *val;
struct elt *next;
} Telt;
int fileAdd(Tfile *, char *);
void fileInit(Tfile *);
void inputReadingAll(Tfile *);
void inputRegistering(Tfile *);
int main(int argc, char **argv){
Tfile file;
fileInit(&file);
inputRegistering(&file);
inputRegistering(&file);
inputReadingAll(&file);
}
int fileAdd(Tfile *F, char *newVal){
Telt *newElt;
newElt = (Telt*)malloc(sizeof(Telt));
if(newElt == NULL){
printf("Error\n");
return 0;
}
newElt->val = newVal;
newElt->next = NULL;
if(fileTaille(F) == 0)
F->first = newElt;
else
F->last->next= newElt;
F->last = newElt;
return 1;
}
void fileInit(Tfile *F){
F->first = NULL;
F->last = NULL;
}
void inputReadingAll(Tfile *file){
printf("> Reading all function\nBEGIN\n");
Telt *currElt = file->first;
while(currElt != NULL){
printf("%p, %s\n", currElt, currElt->val);
currElt = currElt->next;
}
printf("END\n");
}
void inputRegistering(Tfile *file){
printf("> Registering function\n> What to register : \n> ");
char temp[MAXLEN];
fgets(temp, MAXLEN, stdin);
temp[strcspn(temp, "\n")] = 0;
printf("Registering %s\n", temp);
fileAdd(file, temp);
}

Answer 1

The (pointer to) local array temp of the function inputRegistering() is passed to the function fileAdd() and the pointer is directly stored to the structure.
This is bad because the array is local and it is invalidated on returning from the function inputRegistering().
Instead of this, the function fileAdd() should copy the passed string and store the pointer to the copy in the structure.
This can be done like this:
newElt->val = malloc(strlen(newVal) + 1); /* +1 for terminating null-character */
if (newElt->val == NULL) {
printf("Error\n");
free(newElt);
return 0;
}
strcpy(newElt->val, newVal);
instead of this:
newElt->val = newVal;