how to save a directory and file tree

i have made a linked list of the following type which contains directories and files info:

Code:

struct DIR
{
filename // file or directory name
fileID // file or dir ID
ParentID// parent dir's ID
// other info crucial to saving
}

my question is how to save files and directories such that a complete tree is saved?
Please give me some guidelines. I'll be thankfull.

Well, to store a tree, your data structure must be capable of reproducing that tree format. To do so, your DIR struct will likely need to store a pointer to another DIR struct representing the subtrees. You are probably already using such a setup for the linked-list correct? Now we are simply talking about adding another such pointer.

yes the next pointer is already there, which I forgot to mention. what I need is an algo to save the tree.

Code:

struct DIR
{
     filename // file or directory name
     fileID // file or dir ID
     ParentID// parent dir's ID
     // other info crucial to saving
     DIR* next;
}