Question

I am making a linked list program for my basic C assignment.
However, I will always get the force closed error on .exe and get a segmentation fault on Ubuntu.

I tried to break it down and rewrite but I have no idea where the code fails.

I’d appreciate your help.

#include<stdio.h>
#include<stdlib.h>
#include<string.h>


    struct node{
            char name[20];
            int mark;
            struct node *next;

    };

    struct node *addnode(char name[], float mark);


    int main(void){

            int j = 0;
            char StdName[10];
            float StdMarks;

            struct node *head = NULL;
            struct node *curr = NULL;

            head = curr = addnode('\0',0.0);

            for(j=0; j<3; j++){

                    printf("\nEnter StdName >>");

                    printf("\nMarks for %s >>", StdName);


                    curr -> next = addnode("", 5.5);
                    curr = curr->next;
            }

            curr = head -> next;

            j = 0;

            printf("\nnode\tName\tMarks");

            while(curr){

                    printf("\n%d\t%s\t%5.2f", j++, curr->name, curr->mark);
                    curr=curr->next;
            }

    return 0;

    }

    struct node *addnode(char name[], float mark){

            struct node *temp;

            temp=(struct node*)malloc(sizeof(struct node));
            strcpy(temp->name,name);
            temp->mark=mark;
            temp->next=NULL;

    return (temp);
    }

Answer 1

A few mistakes:

• '\0' is not a char[], but a char whose value is 0 and converted to a char* (NULL pointer). Use "" for an empty string. The compiler should have emitted a warning for this. Compile with warning level at highest and treat warnings as errors (so you cannot ignore them). For gcc the flags are -Wall -Werror.
• StdName is not initialised and is never populated but is used in a printf("%s") call.