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POInserting item in the end of list in C, produces a segmentation fault
 

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  1. POInserting item in the end of list in C, produces a segmentation fault
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    <p>I am trying to insert items at the end of a list, however, when i compile it, it does allocate memory for the Record ptr, but it does not insert the items in the end of the list. Segmentation fault.Can anyone help with it? Cheers. </p> <pre><code>#include &lt;stdio.h&gt; #include &lt;stdlib.h&gt; /* these arrays are just used to give the parameters to 'insert', to create the 'people' array */ char names[][10]= {"Simon", "Suzie", "Alfred", "Chip", "John", "Tim", "Harriet"}; int ages[7]= {22, 24, 106, 6, 18, 32, 24}; /* declare your struct for a person here */ typedef struct Record{ char *name; int age; struct Record *next; } Record; //set the head pointer at the start of the list Record *headptr = NULL; static void insert (Record *p, char *s, int n) { /* create a new space for the new person */ Record *ptr =(Record*) malloc(sizeof(Record)); /* check if it is succeeded */ if(ptr == NULL){ abort(); printf("memory allocation fail"); exit(1); }else{ printf("memory allocation to person - %s - \n", s); } //set the data for the new person ptr-&gt;name=s; ptr-&gt;age=n; //ptr= NULL; if(headptr==NULL){ headptr = ptr-&gt;next; ptr=headptr; }else{ while( ptr-&gt;next == NULL) { ptr=ptr-&gt;next; headptr=ptr; } } } int main(int argc, char **argv) { /* declare the people array here */ Record *p=headptr; headptr = NULL; //insert the members and age into the unusage array. for (int i=0; i &lt; 7; i++) { insert (p,names[i], ages[i]); /* do not dereference the pointer */ } /* print out a line before printing the names and ages */ printf("\n"); //set the pointer at the start of the list p = headptr; /* print the people array here*/ for (int i = 0; i &lt; 7; i++, p = p-&gt;next) { printf("The name is: %s, the age is:%i\n", p-&gt;name, p-&gt;age); } /* This is the third loop for call free to release the memory allocated by malloc */ /* the free()function deallocate the space pointed by ptr. */ for(int i=0; i&lt;7;i++){ free(p); } } </code></pre>
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