how do I read a text file in C? then make an array of linked lists from it?

say for a each line in the text file there are several words. I want to read each word, which is separated by space. how do i do that? how do i get each word in the line? each line is treated like a linked list and i want to store it in an array. but how?

for example the text is

jeffrey jake john
charlie emilio martin
drew lucy cameron

i want jeffrey jake and john to be a linked list. charlie emilio martin, another. drew lucy and cameron... so on. each line is a linked list

then i would store these linked list to an array.

but before i can do that. i must know how to read each word in a line.

please help...

thanks

1) First you open the file with fopen
2) Then you get a line using fgets
3) Then you parse the line using sscanf
4) Then you close the file with fclose

The following Code opens a given file and reads the names and puts them in a list.
What you want is a list of lists, something like an array of lists. Think of it and i will help you get the final answer to your problems.

Code:

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

typedef struct _Node
{
	char *name;
	struct _Node *next;
}Node;

typedef struct _List
{
	int ListSize;
	Node *head;
	Node *tail;
}List;

Node *CreateNode(char *name)
{
	Node *n = (Node *)calloc(1, sizeof(Node));
	if(n)
	{
		n->name = strdup(name);
		n->next = NULL;

		return n;
	}
	else
		return NULL;
}

List *CreateList()
{
	List *l = (List *)calloc(1, sizeof(List));
	if(l)
	{
		l->ListSize = 0;
		l->head = NULL;
		l->tail = NULL;
		
		return l;
	}
	else
		return NULL;
}

int ListInsertAtEnd(List *l, char *name)
{
	if(l)
	{
		Node *n = CreateNode(name);
		if(n)
		{
			if(!l->head && !l->tail)
			{
				l->head = n;
				l->tail = n;
			}
			else
			{
				l->tail->next = n;
				l->tail = n;
			}
			//Advance the list size.

			l->ListSize++;

			//Return the Value.
			return 0;
		}
		else
		{
			printf("Memory Error.\n");
			return -1;
		}
	}
	else
	{
		printf("List is NULL.\n");
		return -2;
	}
}
void DumpList(List *l)
{
	Node *n = NULL;
	printf("List has size &#37;d\n", l->ListSize);
	for(n = l->head; n != NULL; n = n->next)
		printf("%s ", n->name);
	printf("\n");
}

void DeleteList(List *l)
{
	Node *p = NULL;
	Node *n = l->head;
	while(n)
	{
		p = n->next;
		free(n->name);
		free(n);
		n = p;
	}
	free(l);
	l = NULL;
}
List *CreateListFromFile(char *filename)
{
	FILE *file = NULL;
	if(!filename)
	{
		printf("Enter a valid filename.\n");
		return NULL;
	}
	else
	{
		List *l = CreateList();
		if(!l)
		{
			printf("Error in Creating an Empty list.\n");
			return NULL;
		}
		else
		{
			if(!(file = fopen(filename, "r")))
			{
				printf("Error can not open %s file.\n", filename);
				DeleteList(l);
				return NULL;
			}
			else
			{
				char *buffer = (char *)calloc(BUFSIZ, sizeof(char));
				if(!buffer)
				{
					printf("Can not create Buffer.\n");
					DeleteList(l);
					return NULL;
				}
				else
				{
					char *token = NULL;
					while(fgets(buffer, BUFSIZ, file) != NULL)
					{
						if(buffer[0] == '\0')
							break;
						if(buffer[strlen(buffer) -1] == '\n')
							buffer[strlen(buffer) -1] = '\0';
						token = strtok(buffer, " ");
						if(token)
						{
							ListInsertAtEnd(l, token);
							while(token)
							{
								token = strtok(NULL, " ");
								if(token)
									ListInsertAtEnd(l, token);
							}
						}
						memset(buffer, 0 , BUFSIZ);
					}
					if(feof(file))
					{
						fclose(file);
						free(buffer);
						return l;
					}
					else
					{
						printf("Earlier break, the file is not read till the end.\n");
						fclose(file);
						free(buffer);
						DeleteList(l);
						return NULL;
					}
				}
			}
		}
	}
}

int main(int argc, char **argv)
{
	List *l = CreateListFromFile("test.txt");
	DumpList(l);
	return 0;
}

The code was writen in Visual Studio 2005, of course i suppose there are bugs..

Printed results using file "test.txt"

List has size 5
kostas nikos ilias baggelis giannis
Press any key to continue . . .

The names are in greek, can change them to anything, use a file named test.txt in your project directory and give names.

e.g "test.txt"

kostas niikos ilias baggelis giannis\n

hmmm.. how do i exactly read by line then parse it? i don't know the syntax...

Read the first reply over and check the links out.

Code:

hmmm about the linked lists, is this correct? 

typedef struct UrlList    
        {char *url;
         struct UrlList *Unext;
         } SiteList;

 UrlList *uHead, *uTail;

 main()
 {
 char name[2];
 name[0] = "john";
 name[1] = "mark";
 name[2] = "matthew";

for (i=0; i=2; i++)
 {
 char *newword = name[i];
 UrlList *newnode = malloc (sizeof(UrlList));  // should i put SiteList after UrlList?
    newnode->next = NULL;
    uHead = newnode;
    uTail = uHead;
  }
---if i access each element, is this correct?

UrlList *tmp;
     tmp = head;
     while (tmp!=NULL)
     {
           printf ("%s \n ", tmp->url);
           tmp = tmp->next;
     }
 else
  {
    newnode->url = newword;
    newnode->next = NULL;
    uTail = newnode;
  }
 }

}


//but how will i know that i am referring to the linked list SiteList?