wrong order

[BigEvil]

Add a recursive readnum() function

void linklist::readfile()
{
	ifstream myFile("textfile.txt");
        readnum();
	myFile.close();
	cout << "All the data has been read from the file." << '\n';
	cout << "Press Enter to continue!" << '\n';
	getch();
}
void linklist::readnum()
{
    if(myFile)
    {
        int s;
        myFile>>s;
        readnum();
        this->additem(s);   // Number read first will be added last
    }
}

Or instead of the recursive method, instead of adding the new node at the beginning of the list, add it at the end.

node *n = new node;
n->info = number read from file;
n->next = NULL;
node *end = first;    // first (or list) = pointer to beginning of the list
if(end==NULL)   // If list is empty
    first = n, end = n;
else
{
    while(end->next !=NULL)   //Traverse to last node of list
        end = end->next;
   end->next = n;  // Add new node after the last node
}

First one will be faster I guess, coz you won't have to traverse to the end of the list each time, but it will consume more memory (you can keep a pointer to end node in 2nd method, but it might make the code more complicated).