#!/usr/bin/env perl
use 5.012;
use strict;
use warnings;
use Data::Dumper qw(Dumper);

my $str = &listfiles('<directory>');
print Dumper \$str;


use Inline C => <<'END_OF_C_CODE';
#include <dirent.h>     /* Defines DT_* constants */
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/syscall.h>

#define handle_error(msg) do { perror(msg); exit(EXIT_FAILURE); } whil
+e (0)

struct linux_dirent {
   long           d_ino;
   off_t          d_off;
   unsigned short d_reclen;
   char           d_name[];
};

#define BUF_SIZE 1024*1024*5
SV* listfiles(const char * dir) {
   int fd, nread;
   char buf[BUF_SIZE];
   struct linux_dirent *d;
   int bpos;
   char d_type;
   char inode;
   HV* hash = newHV();

   fd = open(dir, O_RDONLY | O_DIRECTORY);
   if (fd == -1) handle_error("open");
   for ( ; ; ) {
       nread = syscall(SYS_getdents, fd, buf, BUF_SIZE);
       if (nread == -1) handle_error("getdents");
       if (nread == 0) break;
       for (bpos = 0; bpos < nread;) {
           d = (struct linux_dirent *) (buf + bpos);
           if (d->d_ino != 0) {
               size_t nbytes = snprintf(NULL, 0, "%d", d->d_ino) + 1;
               char *inode = malloc(nbytes);
               snprintf(inode, nbytes, "%d", d->d_ino);
               hv_store(hash, inode, strlen(inode), newSVpvf("%s",(cha
+r *) d->d_name, 0), 0);

           }
           bpos += d->d_reclen;
       }
   }
return newRV_noinc((SV*) hash);
}
END_OF_C_CODE
[download]

I added a second loop to list the files recursively, next in line is C multi threads and another sub hash to divide the record types easily.

#!/usr/bin/env perl
use 5.012;
use strict;
use warnings;
use Data::Dumper qw(Dumper);

my $str = &listfiles('<directory>');
print Dumper \$str;

use Inline C => <<'END_OF_C_CODE';
#include <dirent.h>     /* Defines DT_* constants */
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/syscall.h>

#define handle_error(msg) do { perror(msg); exit(EXIT_FAILURE); } whil
+e (0)

struct linux_dirent {
   long           d_ino;
   off_t          d_off;
   unsigned short d_reclen;
   char           d_name[];
};

#define BUF_SIZE 1024*1024*5
SV* listfiles(const char * dir) {
   int fd, nread;
   struct linux_dirent *d;
   int bpos;
   char inode, d_type;
   char * buf = malloc(BUF_SIZE);
   static HV* hash;

   if (!(hash)) hash = newHV();
   fd = open(dir, O_RDONLY | O_DIRECTORY);
   if (fd == -1) handle_error("open");
   for ( ; ; ) {
       nread = syscall(SYS_getdents, fd, buf, BUF_SIZE);
       if (nread == -1) handle_error("getdents");
       if (nread == 0) break;
        for (bpos = 0; bpos < nread;) {
            d = (struct linux_dirent *) (buf + bpos);
            d_type = *(buf + bpos + d->d_reclen - 1);
            bpos += d->d_reclen;
            if(d->d_ino && strcmp(d->d_name, ".") && strcmp(d->d_name,
+ "..") && strcmp(d->d_name, ".snapshot")) {
               size_t nbytes = snprintf(NULL, 0, "%d", d->d_ino) + 1;
               char *inode = malloc(nbytes);
               snprintf(inode, nbytes, "%d", d->d_ino);
               hv_store(hash, inode, strlen(inode), newSVpvf("%s/%s",(
+char *) dir,d->d_name, 0), 0);
                if(d_type == DT_DIR) {
                    int dir_len = strlen(dir);
                    char * subdir = calloc(1, PATH_MAX + 1);
                    strcat(subdir, dir);
                    strcat(subdir + dir_len, "/");
                    strcat(subdir + dir_len + 1, d->d_name);
                    listfiles(subdir);
                    free(subdir);
                }
            }
        }
    }
   close(fd);
   free(buf);
return newRV_noinc((SV*) hash);
}
END_OF_C_CODE
[download]