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POfread not working while reading structure dynamically from a file
 

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  1. POfread not working while reading structure dynamically from a file
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    <p>I am creating a linked list then writing it to a file and reading it again. I am using fwrite and fread to write and read a whole instance of a structure at a time. But the problem is it is not working correctly. I suppose writing is working fine after seeing the output file but still not sure about it. But reading is not working at all.</p> <p>Below is structure</p> <pre><code>struct student { int roll_num; char name[100]; struct student *next; }; </code></pre> <p>Below is logic</p> <pre><code>ifd = fopen("qwer1234.txt","wb"); struct student *temp; temp = start; while(temp != NULL) { fwrite(temp, sizeof(struct student), 1, ifd); temp = temp-&gt;next; } close(ifd); ifd = fopen("qwer1234.txt","rb"); temp = NULL; temp = malloc(sizeof(struct student)); fread(temp, sizeof(struct student), 1, ifd); start = temp; //temp-&gt;next = NULL; printf("%s\t%d\n",temp-&gt;name,temp-&gt;roll_num); temp = malloc(sizeof(struct student)); /*while(fread(temp, sizeof(struct student), 1, ifd) == 1) { temp-&gt;next = start; start = temp; printf("%d/n",temp-&gt;roll_num); temp = malloc(sizeof(struct student)); }*/ close(ifd); </code></pre> <p>Although I am only reading a single instance for the time being, it is still not working. Nothing gets stored in the temp->name and 0 gets stored in temp->roll_num. I am stuck on it for last 4 hours. I can do it by storing elements of structure individually but wanted to do by a different way this time. </p> <p>And for all those for whom it matters, this is a homework question.</p> <p>Any help would be greatly appreciated. Thanks :)</p>
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