Append a string from fscanf to linked list in C -

i want read file , put each words in linked list. when read file, linked list have number of nodes node equal last word.

an example, if text file :

hello sir 

my linked list :

[sir,sir,sir] 

and should :

[hello, good, sir] 

my main.c

#include <stdio.h> #include <stdlib.h> #include <string.h> #include <assert.h>  typedef struct nodetag {   char *data;   struct nodetag *next; } node;  node *node_create();  typedef struct listtag {   struct nodetag *first; } list;  list *list_create(); void list_append(list *list, char *str); void list_print(list *list);  int main(void) {   char word[100];   file *file = fopen("file.txt", "r");    if(file == null) {     printf("error in opening file\n");     return 1;   }    list *l = list_create();    while(fscanf(file, "%s", word) == 1){     list_append(l, word);   }   return 0; } 

here functions. removed destroy , free functions make more clear.

node *node_create() {   node *node = malloc(sizeof(node));   assert(node != null);    node->data = "";   node->next = null;    return node; }  list *list_create() {   list *list = malloc(sizeof(list));   assert(list != null);    node *node = node_create();   list->first = node;    return list; }  void list_append(list *list, char *str) {   assert(list != null);   assert(str != null);    node *node = list->first;   while (node->next != null) {   node = node->next;   }    node->data = str;   node->next = node_create(); }  void list_print(list *list) {   assert(list != null);    printf("[");   node *node = list->first;   while (node->next != null) {     printf("%s", node->data);     node = node->next;     if (node->next != null) {       printf(", ");     }   }   printf("]\n"); } 

if this, work properly. guess append pointer of word pointing same place again , again ?

    list_append(l, "test1");     list_append(l, "test2"); 

output :

   [test1, test2] 

notice in main, have 1 buffer storing strings:

char word[100]; 

you pass word parameter list_append method, during write

node->data = str; 

this means of nodes pointing word buffer in main string, of them display same string.

to fix this, need duplicate buffer somewhere. i'd recommend doing this:

node->data = strdup(str); 

there may other issues in code, you'll need fix before move on. try updating , see if resolves issue. @sean bright points out, seems you're overwriting wrong string pointers when append, you'll need fix well.

hope helps!