Why does the following recursive directory creation fail?



  • i have posted this same question on stackoverflow and i got as far as shown. But still i have some errors(synactical and logical) which i couldn't solve at all.
    May be i can get some help here;

    i expect to have more than one million files with unique names. I have been told that if i put all this files in one or two directories the search speed for these files will be extremely slow. So i have come up with the following directory architecture.

    I want the directory structure to branch out with 10 sub directories and the level of the sub directories will be 4. because the file names are guaranteed to be unique i want to use these file names to make hashes which can be used to put the file in a directory and also later to find it. The random hash values will make a directory to have,approximately, 1,000 files.

    so if F is root directory then inserting or searching for a file will have to go through these steps:

    I want to use numbers from 0-9 as directory names

    h=hash(filename)
    sprintf(filepath,"f//%d//%d//%d//%d//.txt",h,h,h,h);
    HOW DO I CREATE THESE DIRECTORIES?

    EDIT:

    All the files are text files. The program will be distributed to many people in order to collect information for a research. So tt is important that these files are created like this.
    @#include<iostream>
    #include<stdlib.h>

    #include<windows.h>
    #include<stdio.h>

    void make_dir(int depth, char *dir) {
    if (depth < 4) {
    CreateDirectoryA (dir,NULL);
    for (int i = 0; i < 10; i++) {
    char sdir= (char)malloc(strlen(dir+10)); // XXX 10?
    strcpy(sdir, dir);
    printf("%s\n", sdir);
    CreateDirectoryA(sdir,NULL);
    make_dir(depth + 1, sdir);
    free(sdir);
    }
    }

    }

    int main()
    {
    make_dir(0,"dir");
    return 1;
    }@



  • Being in a Qt forum, I come up with a Qt base solution:

    @
    QString filePath = QString("f/%1/%2/%3/%4/%5")
    .arg(dirHash1)
    .arg(dirHash2)
    .arg(dirHash3)
    .arg(dirHash4)
    .arg(fileName);

    QFileInfo fi(filePath);
    QDir dir = fi.absoluteDir();
    if(!dir.exists())
    dir.mkpath(fi.absoluteDirPath());

    QFile file(filePath);
    @


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