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POReading File Data Into a Linked List in C
 

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    <p>I am trying to create a simple phonebook program that reads data from a file and stores the content into specific nodes in the list. It works fine if I use my addEntry function with static data, such as:</p> <pre><code>addEntry("First", "Last", "555-555-5555"); </code></pre> <p>If I try to read more than 1 entry from the file, each entry just appears to be whatever the last entry was in the file. For example, if my file contained:</p> <pre><code>First1 Last1 123-456-7890 First2 Last2 987-654-3210 </code></pre> <p>After storing the data in the list and printing, the output would look like:</p> <pre><code>First2 Last2 987-654-3210 First2 Last2 987-654-3210 </code></pre> <p>Rather than printing each specific name and number. This confuses me because this issue only occurs when I read data from the file, not when I manually type in the name and number in a function call. Here are the definitions for main and addEntry, thank you in advance.</p> <pre><code>#include &lt;stdlib.h&gt; #include &lt;stdio.h&gt; struct bookNode { char * firstName; char * lastName; char * phoneNumber; struct bookNode * next; } * head; FILE * fpointer; void addEntry(char * fn, char * ln, char * pn); void display(); int numEntries(); void writeBookData(struct bookNode * selection); int main() { head = NULL; addEntry("Test", "Name", "111-111-1111"); addEntry("Test2", "Name2", "222-222-2222"); // These entries will work as intended int i; fpointer = fopen("addressbook.dat", "a+"); if(fpointer == NULL) { printf("Error: addressbook.dat could not be opened.\n"); } char first[20]; char last[20]; char num[20]; while (!feof(fpointer)) { fgets(first, 20, fpointer); fgets(last, 20, fpointer); fgets(num, 20, fpointer); //Removes newline characters from the ends of the names i = 0; while(first[i] != '\n') { i++; } first[i] = '\0'; i = 0; while(last[i] != '\n') { i++; } last[i] = '\0'; // Adds the entry from the strings with the file data in them addEntry(first, last, num); } fclose(fpointer); display(); // typical linked list display function int entryCount = numEntries(); printf("There are %d entries in this Address Book\n", entryCount); return EXIT_SUCCESS; } void addEntry(char * fn, char * ln, char * pn) { struct bookNode * tempNode, * iterator; tempNode = (struct bookNode *)malloc(sizeof(struct bookNode)); tempNode-&gt;firstName = fn; tempNode-&gt;lastName = ln; tempNode-&gt;phoneNumber = pn; iterator = head; // If the list is empty if (head == NULL) { head = tempNode; head-&gt;next = NULL; } // The list is not empty else { while(iterator-&gt;next != NULL) { iterator = iterator-&gt;next; } tempNode-&gt;next = NULL; iterator-&gt;next = tempNode; } } </code></pre>
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