How can I iterate over files in a given directory?

Question

I need to iterate through all .asm files inside a given directory and do some actions on them.

How can this be done in a efficient way?

Answer 1

Original answer:

import os

for filename in os.listdir(directory):
    if filename.endswith(".asm") or filename.endswith(".py"): 
         # print(os.path.join(directory, filename))
        continue
    else:
        continue

Python 3.6 version of the above answer, using os - assuming that you have the directory path as a str object in a variable called directory_in_str:

import os

directory = os.fsencode(directory_in_str)
    
for file in os.listdir(directory):
     filename = os.fsdecode(file)
     if filename.endswith(".asm") or filename.endswith(".py"): 
         # print(os.path.join(directory, filename))
         continue
     else:
         continue

Or recursively, using pathlib:

from pathlib import Path

pathlist = Path(directory_in_str).glob('**/*.asm')
for path in pathlist:
     # because path is object not string
     path_in_str = str(path)
     # print(path_in_str)

• Use rglob to replace glob('**/*.asm') with rglob('*.asm')
  • This is like calling Path.glob() with '**/' added in front of the given relative pattern:

from pathlib import Path

pathlist = Path(directory_in_str).rglob('*.asm')
for path in pathlist:
     # because path is object not string
     path_in_str = str(path)
     # print(path_in_str)