Thread: Linked List Sorting

Hey there,

I need help as i'm new in C.
I have a linked list that i'm posting here but i need to know if it's good first.

Secondly i want to know how to scan a group of words in one line and after pressing enter i want the words to be printed.
I guess this has to be in my main.. no idea how to do that

Hope i'm clear

Code:

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


typedef struct info
{
    void *data;      
    struct info *next; 
}INFO;




/*---------------CREATING THE NODE-------------*/


INFO *list_create(void *data)              
{
    INFO *node;                             
    if (!(node=malloc(sizeof(INFO))))       
        return NULL;
    node->data=data;
    node->next=NULL;                        
    return node;
}


/*--------------INSERTING THE NODES-------------*/


INFO *list_insert(INFO *node, void *data)  
{
    INFO *new_node;                         
    new_node = list_create(data);         
    new_node->next = node->next;          
    node->next = new_node;
    return new_node;
}


/*-------------INSERT AT BEGINNING-------------*/


INFO *list_insert_beg(INFO *list, void *data)
{
    INFO *new_node;
    new_node = list_create(data);       
    new_node->next = list;
    return new_node;
}


/*-------------REMOVING THE NODE--------------*/


int list_remove(INFO *list, INFO *node)            
{
    while (list->next && list->next != node)
        list = list->next;
    
    if (list->next)
    {
        list->next = node->next;
        free(node);
        return 0;
    }
    else
    {
        return -1;
    }
}


/*------------------------OPERATION ON LIST------------------*/


/*----------TRAVERSING THE LIST----------------*/


int list_trav_each(INFO *node, int(*func)(void*))
{
    while (node)
    {
        if (func(node->data)!=0)
            return -1;
        node = node->next;
    }
    return 0;
}


/*-----------SEARCHING THE LIST------------*/

INFO *list_find(INFO *node, int(*func)(void*,void*), void *data)
{
    while (node)
    {
        if(func(node->data, data)>0)
            return node;
        node=node->next;
    }
    return NULL;
}

Thanks for the help

It looks OK to me, but take that with a grain of salt, because I don't know a whole lot about your code.

You should write comments explaining details about the func pointers, at the very least. What do they return, what does the return value mean, and how do you call the function pointer? All of these questions are important because they dictate to the person using the code how to write the functions you are going to use in callbacks.

At a glance I can see you will have a memory leak, since in the remove function you free only the node and not the data.

Actually that should be implemented in callbacks. Since it is the user's data, freeing the data is not necessarily as simple as calling free.

In addition to iMalc's comment, you can't remove the first node of your list.

Bye, Andreas