The permissions of a file in a Linux system are split into three sets of three permissions: read, write, and execute for the owner, group, and others. Each of the three values can be expressed as an octal number summing each permission, with 4 corresponding to read, 2 to write, and 1 to execute. Or it can be written with a string using the lette…

gistfile1.py

def octal_to_string(octal): 
    result = "" 
    value_letters = [(4,"r"),(2,"w"),(1,"x")] 
    #Iterating over each digit in octal 
    for digit in [int(n) for n in str(octal)]: 

        #Checking for each of permission values 
        for value, letter in value_letters: 
            if digit >= value: 
                result += letter 
                digit -= value 
            else: 
                result += "-" 
    return result 
    
print(octal_to_string(755)) # Should be rwxr-xr-x
print(octal_to_string(644)) # Should be rw-r--r--
print(octal_to_string(750)) # Should be rwxr-x---
print(octal_to_string(600)) # Should be rw-------

hello RabeyaMuna
At the 5th line, i don't getting it !
Can you explain me ?

hello RabeyaMuna At the 5th line, i don't getting it ! Can you explain me ?

using for loop, each digit in the octal value is taken an a single digit. Example: for the octal value 755, 7 is taken through the for loop and evaluated against the values one by one like 7>=4 and so on

for digit in (octal):
TypeError: 'int' object is not iterable

#hence converted to str
for digit in [int(n) for n in str(octal)]: