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POSearching through a linked list in C
 

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    <p>I have been working on a function <code>searchn()</code> which takes in a linked list <code>list</code> and a string <code>lname</code>.</p> <p>It compiles perfectly fine, but I get a segmentation fault (core dumped) when I try running the function. I ran it through Valgrind and it tells me that I'm using <code>strcpy</code> and <code>strcmp</code> incorrectly. My struct for <code>player</code> has also been included for reference. Can anybody see what I'm doing wrong? Sorry, I'm not the most proficient in coding. </p> <p>Any help would be great. Thanks. </p> <pre><code>struct player { char* fname; char* lname; char pos; int val; int rank; struct player* next; }; void searchn(struct player* list, char* lname){ while (list!=NULL &amp;&amp; strcmp(list-&gt;lname, lname) != 0){ list = list-&gt;next; } if (list != NULL &amp;&amp; strcmp(list-&gt;lname, lname)==0) { printf("%s found! \n", lname); printf("%s \n", list-&gt;lname); printf("%s \n", list-&gt;fname); printf("%c \n", list-&gt;pos); printf("%d \n", list-&gt;val); printf("\n"); } } </code></pre> <p>The following is how the method that populates the linked list. </p> <pre><code>void addp (struct player* newnode, struct player* list){ struct player* templist1; // if the list is non empty. if (list !=NULL){ if(newnode-&gt;pos == GOALKEEPER){ //insert if G. while (list-&gt;next != NULL &amp;&amp; (list-&gt;next)-&gt;rank &lt; 1){ list = list-&gt;next; } templist1 = list-&gt;next; list-&gt;next = newnode; newnode-&gt;next = templist1; } if(newnode-&gt;pos == DEFENDER){// after G bef M. // iterate through templist. while (list-&gt;next != NULL &amp;&amp; (list-&gt;next)-&gt;rank &lt; 2) { // go to end of G. // when the list isn't empty next node rank is less than one, keep going list = list -&gt; next; } // when finally rank == or &gt; 1, then add newnode. templist1 = list-&gt;next; list-&gt;next = newnode; newnode-&gt;next = templist1; } if(newnode-&gt;pos == MIDFIELDER){ //after G and M but before S while (list-&gt;next != NULL &amp;&amp; (list-&gt;next)-&gt;rank &lt; 3) { list = list -&gt; next; } // when stopped, then add newnode. templist1 = list-&gt;next; list-&gt;next = newnode; newnode-&gt;next = templist1; } if(newnode-&gt;pos == STRIKER){ // at the end. while (list-&gt;next != NULL &amp;&amp; (list-&gt;next)-&gt;rank &lt; 4){ list = list -&gt; next; } templist1 = list-&gt;next; list-&gt;next = newnode; newnode-&gt;next = templist1; } printf("player added"); } } </code></pre>
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    1. COYou're going to need to show how you allocated and assigned the values in your link list elements. There's something wrong in that logic probably that's causing your segmentation fault.
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    2. COI guess it's that, but the thing is that the method which populates the linked list has work fine so far. I have another search method which searches through each node's `int val` which happens to work fine.
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    3. COYou'll still need to show how the strings and the structs are allocated for a complete picture of what's going on. And how the strings are copied into the structs. Any one of those could yield a segmentation fault.
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