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Linked list in c (read from file)

I'm very new to C-programming, and I'm having some difficulties. I'm trying to read line from line to a text file, and then add each line to a simple linked list. I have tried a lot, but I haven't found a solution. So far in my code I'm able to read from the file, but I can't understand how to save the text line for line and add it to the linked list.

This is what I have so far:

struct list {
char string;
struct list *next;
};

typedef struct list LIST;

int main(void) {

    FILE *fp;
    char tmp[100];
    LIST *current, *head;
    char c;
    int i = 0;
    current = NULL;
    head = NULL;
    fp = fopen("test.txt", "r");

    if (fp == NULL) {
        printf("Error while opening file.\n");
        exit(EXIT_FAILURE);
    }

    printf("File opened.\n");

    while(EOF != (c = fgetc(fp))) {
       printf("%c", c);
    }

    if(fclose(fp) == EOF) {
        printf("\nError while closing file!");
        exit(EXIT_FAILURE);
    }
    printf("\nFile closed.");
}

If anyone could give me some pointers on what I need to do next to make it work, I would highly appreciate it. I'm used to Java, and somehow my brain can't understand how to do these things in C.

like image 682
user16655 Avatar asked Oct 20 '22 02:10

user16655


1 Answers

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

struct list {
    char *string;
    struct list *next;
};

typedef struct list LIST;

int main(void) {
    FILE *fp;
    char line[128];
    LIST *current, *head;

    head = current = NULL;
    fp = fopen("test.txt", "r");

    while(fgets(line, sizeof(line), fp)){
        LIST *node = malloc(sizeof(LIST));
        node->string = strdup(line);//note : strdup is not standard function
        node->next =NULL;

        if(head == NULL){
            current = head = node;
        } else {
            current = current->next = node;
        }
    }
    fclose(fp);
    //test print
    for(current = head; current ; current=current->next){
        printf("%s", current->string);
    }
    //need free for each node
    return 0;
}
like image 60
BLUEPIXY Avatar answered Oct 23 '22 01:10

BLUEPIXY