exit the chroot

gistfile1.txt

//create first a directory called chroot!

#include <unistd.h>
#include <stdlib.h>
#include <fcntl.h>
#include <dirent.h>
#include <stdio.h>
#include  <sys/types.h>

void printDirInformation(DIR* dir) {
    char* name;
    struct dirent* current_dir;
    do {
        current_dir = readdir(dir);
        if(current_dir != NULL) {
            name = current_dir->d_name;
            printf("%s\n", name);
        }
    } while(current_dir != NULL );
}

int main() {

    int fd;
    fd = open(".", O_RDONLY);
    chdir("chroot");
    int ret = chroot(".");
    if(ret == -1) {
        printf("cannot enter in chroot\n");
        exit(1);
    }
    printf("open first chroot\n");
    DIR *dir = opendir(".");
    if(dir != NULL)
        printDirInformation(dir);

    printf("open second chroot\n");
    fchdir(fd);
    chroot(".");
    dir = opendir(".");
    if(dir != NULL)
        printDirInformation(dir);
    return 0;
}