Second theoretical presentation.

There is the presentation of the theoretical part

Segunda presentacionteoricanachos

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This is for the File System part..


All we know how the file systems works like a tree.

In this moment all know about NTFS, ext3 and ext4 so i just add a little description. (if you want the there are links to wikipedia for read more about FS, etc) 

NTFS supersedes the FAT file system as the preferred file system for Microsoft’s Windows operating systems. NTFS has several improvements over FAT and HPFS  such as improved support for metadata and the use of advanced data structures to improve performance, reliability, and disk space utilization, plus additional extensions such as security access control lists (ACL) and file system journaling.


The ext3 is a journaled file system that is commonly used by the Linux kernel. It is the default file system for many popular Linux distributions, including Debian. Stephen Tweedie first revealed that he was working on extending ext2

 ext4 developed as the successor to ext3. Was included in version 2.6.19 of the Linux kernel.


To edit files in code we need to implement
open(Open the file)
read(Read the file)
write(Write file)
close(Close file)
delete(Delete file)
append(add )
seek(Search)
rename(Change name)

So we make a code to compare the size of all the files in some directory's

#!/usr/bin/python
f = open(archivoEntrada, "r")
lineas = f.readlines()
numeros = []
bytes = []
kbytes = []
mbytes = []
for linea in lineas:
    num = linea.strip()
    if len(num) > 0:
        if len(num) > 1:
            id = num[-1]
            restante = num[:-1]
            if restante.isdigit():
                if id == 'K':
                    kbytes.append(num)
                elif id == 'M':
                    mbytes.append(num)
                else:
                    bytes.append(num)
            #print linea[:-2]
           
nbytes = 0
nMbytes = 0
nKbytes = 0

for byte in bytes:
    nbytes += 1
    numero = int(round(float(byte[:-1])))
    numeros.append(numero)
for kbyte in kbytes:
    nKbytes += 1
    numero = int(round(float(kbyte[1:-1])))*1024
    numeros.append(numero)
    
for mbyte in mbytes:
    nMbytes += 1
    numero = int(round(float(mbyte[1:-1])))*1024*1024
    numeros.append(numero)


distintos = {}
for num in numeros:
    if num not in distintos:
        distintos[num] = 1
    else:
        distintos[num] +=1
        

resultados = distintos.items()

for res in resultados:
    print "%d\t %d"%(res[0], res[1])

We select home, usr, sbin and lib.
Red point = each file
y = frequencies of files with the same size
x = Files size on kbytes

../home

../usr

../sbin

../lib

Saludos..
Jorge - Jose - Richi