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POC, creating one way linked list from file
 

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  1. POC, creating one way linked list from file
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    <p>Got it working. I'm just dumb and wrote <code>=</code> instead <code>==</code> in one place t.t Thanks all.</p> <p>I have file with my data, and now i want to read it and put it into list. I don't fully know how to do it and since I have to finish this project in near future I simply ask you for help ;]</p> <p>header file:</p> <pre><code>typedef struct { char category[50]; char name[50]; char ingredients[50]; char instruction[1000]; }recipe_t; typedef struct element { struct element *next; recipe_t recipe; } el_list; void all_recipe_list(); void show_all_list(el_list *list); void add_new_element_to_list(el_list *list, recipe_t formula); </code></pre> <p>my list functions file:</p> <pre><code>void all_recipe_list() //reading all record into list + show it(show_all_list function) { FILE *database; recipe_t formula; el_list *head; head = NULL; database = fopen(filename, "rb"); fgetc(database); // function feof returns value only if we read something before, so in order to check if its end, we try to read one char // when writing data to file, I put \n always before new record while (!feof(database)) { fread(&amp;formula, sizeof(recipe_t),1,database); if (head == NULL) { head = malloc(sizeof(el_list)); head-&gt;recipe = formula; head-&gt;next = NULL; } else { add_new_element_to_list(head,formula); } fgetc(database); // same as above } fclose(database); show_all_list(head); } void show_all_list(el_list *list) { el_list *p=list; while (p != NULL) { printf("Kategoria:%s\n", p-&gt;recipe.category); printf("Nazwa:%s\n", p-&gt;recipe.name); printf("Skaldniki:%s\n", p-&gt;recipe.ingredients); printf("Instrukcja:%s\n", p-&gt;recipe.instruction); p = p-&gt;next; } } void add_new_element_to_list(el_list *list, recipe_t formula) { el_list *p, *new_el; p = list; while (p-&gt;next != NULL) { p = p-&gt;next; } new_el = malloc(sizeof(el_list)); new_el-&gt;recipe = formula; new_el-&gt;next = NULL; p-&gt;next= new_el; } </code></pre> <p>What are the problems? Program is compiling allright but it's crashing when all_recipe_list is called. It's probably something wrong with add_new_element_to_list. Can't figure out what though. Also I don't know if in show_all_list p->recipe.category is right way to do it.</p>
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    1. USNihu
    1. USNihu
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    1. COThere's an error in `add_new_element_to_list` that jumps right out- what's the line `new_el->recipe;` doing? Also, you can probably just remove `p` altogether and use the `list` pointer.
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      1. POC, creating one way linked list from file
      1. USLeigh
    2. COI like this line `new_el->recipe;`.
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      1. USalk
    3. CODon't use `feof` like that - just check the return value of your `fread` call.
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      1. POC, creating one way linked list from file
      1. USCarl Norum
 

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