Create directories, read files and create file

I have this program in C++ (but even Python) which opens or creates a directory called file_path, scrolls each text file which goes along the Data_xyzw.txt format, finds the bigger xyzw and creates a name which is Data_abcd.txt where abcd = xyzw+1:

extern "C" void file_digits_finder (char* file_path){
    //creating folder
    int status = 0;
    status = mkdir(file_path, S_IRWXU | S_IRWXO);

    //getting names from all files in folder if already existent
    uint higher_number = 0;
    if (status==-1){
        DIR *folder;
        struct dirent *entry;
        int files = 0;

        folder = opendir(file_path);
    //  All files will be of type: Data_xyzw, so 5 nondigit and 4 digits

        while( (entry = readdir(folder)) ){
            uint file_number = 0;
            if ( isdigit(entry->d_name[5])!=0 && isdigit(entry->d_name[6])!=0 && isdigit(entry->d_name[7])!=0 && isdigit(entry->d_name[8])!=0){
                string digits = to_string(entry->d_name[5]-48) + to_string(entry->d_name[6]-48) + to_string(entry->d_name[7]-48) + to_string(entry->d_name[8]-48) ;
                file_number = stoi(digits);
            if (higher_number < file_number){
                higher_number = file_number;
            //file will all be of the same name "Data" + a "file_number". We want to create a new file.

    //decing file_number
    previous_file_digits = higher_number;

How can I write this in julia?

I think with these functions you get all you need: