Question

While checking the efficiency of os.walk, I created 6,00,000 files with the string Hello <number> (where number is just a number indicating the number of the file in the directory), e.g. the contents of the files in the directory would look like:-

File Name | Contents
1.txt     | Hello 1
2.txt     | Hello 2
.
.
600000.txt|Hello 600000

Now, I ran the following code:-

a= os.walk(os.path.join(os.getcwd(),'too_many_same_type_files')) ## Here, I am just passing the actual path where those 6,00,000 txt files are present
print a.next()

---

The problem what I felt was that the a.next() takes too much time and memory, because the 3rd item that a.next() would return is the list of files in the directory (which has 600000 items). So, I am trying to figure out a way to reduce the space complexity (at least) by somehow making a.next() to return a generator object as the 3rd item of the tuple, instead of list of file names.

Would that be a good idea to reduce the space complexity?

Answer 1

As folks have mentioned already, 600,000 files in a directory is a bad idea. Initially I thought that there’s really no way to do this because of how you get access to the file list, but it turns out that I’m wrong. You could use the following steps to achieve what you want:

1. Use subprocess or os.system to call ls or dir (whatever OS you happen to be on). Direct the output of that command to a temporary file (say /tmp/myfiles or something. In Python there’s a module that can return you a new tmp file).

2. Open that file for reading in Python.

3. File objects are iterable and will return each line, so as long as you have just the filenames, you’ll be fine.