Question

Execute a recursive directory traversal. As walking the file tree, you will be looking for duplicate files and creating symbolic links to them.

To accomplish directory traversal, you should write a recursive function using the dir family of functions: opendir(), readdir(), chdir() and closedir(). A prototype could look something like this-

void find_unique_files(const char*, char**);

The function have to take a character array representing a filename and an array of strings. If it is known on a directory, it should move into that directory and continue its traversal. If it is known on a text file, it has to generate a hash for text file, check the list of hashes to make sure that it does not already contain that hash, and then insert it if it doesn't. If it does, you know that you have found a duplicate.

The file's hash will be designed using the SHA1 hashing algorithm. A library for calculating this hash is able to be found in .

When a duplicate file is discovered, you will create a symbolic link to duplicate (the one which cannot be added to the list) in the /dups directory using the symlink() function

Symlink - pathname to a file, in fact a string.