IOError: [Errno 2] No such file or directory trying to open a file

Question

I am very new to Python so please forgive the following basic code and problem, but I have been trying to figure out what is causing the error I am getting (I have even looked at similar threads on S.O.) but can't get past my issue.

Here is what I am trying to do:

• loop through a folder of CSV files
• search for a 'keyword' and delete all lines containing the 'keyword'
• save output to a separate folder

Here is my code:

import os, fnmatch
import shutil

src_dir = "C:/temp/CSV"
target_dir = "C:/temp/output2"
keyword = "KEYWORD"

for f in os.listdir(src_dir):
    os.path.join(src_dir, f)
    with open(f):
        for line in f:
            if keyword not in line:
                write(line)
                shutil.copy2(os.path.join(src_dir, f), target_dir)

Here is the error I am getting:

IOError: [Errno 2] No such file or directory: 'POS_03217_20120309_153244.csv'

I have confirmed that the folder and file do exist. What is causing the IOError and how to I resolve it? Also, is there anything else wrong with my code that would prevent me from performing the entire task?

Answer 1

Hmm, there are a few things going wrong here.

for f in os.listdir(src_dir):
    os.path.join(src_dir, f)

You're not storing the result of join. This should be something like:

for f in os.listdir(src_dir):
    f = os.path.join(src_dir, f)

This open call is is the cause of your IOError. (Because without storing the result of the join above, f was still just 'file.csv', not 'src_dir/file.csv'.)

Also, the syntax:

with open(f): 

is close, but the syntax isn't quite right. It should be with open(file_name) as file_object:. Then, you use to the file_object to perform read or write operations.

And finally:

write(line)

You told python what you wanted to write, but not where to write it. Write is a method on the file object. Try file_object.write(line).

Edit: You're also clobbering your input file. You probably want to open the output file and write lines to it as you're reading them in from the input file.

See: input / output in python.

Answer 2

Even though @Ignacio gave you a straightforward solution, I thought I might add an answer that gives you some more details about the issues with your code...

# You are not saving this result into a variable to reuse
os.path.join(src_dir, f)
# Should be
src_path = os.path.join(src_dir, f)

# you open the file but you dont again use a variable to reference
with open(f)
# should be
with open(src_path) as fh

# this is actually just looping over each character 
# in each result of your os.listdir
for line in f
# you should loop over lines in the open file handle
for line in fh

# write? Is this a method you wrote because its not a python builtin function
write(line)
# write to the file
fh.write(line)

Answer 3

Um...

with open(os.path.join(src_dir, f)) as fin:
    for line in fin:

Also, you never output to a new file.

Answer 4

I solved the problem like so:

src_dir = "C:\\temp\\CSV\\"
target_dir = "C:\\temp\\output2\\"
keyword = "KEYWORD"

for f in os.listdir(src_dir):
    file_name = os.path.join(src_dir, f)
    out_file = os.path.join(target_dir, f)
    with open(file_name, "r+") as fi, open(out_file, "w") as fo:
        for line in fi:
            if keyword not in line:
                fo.write(line)

Answer 5

I got this error and fixed by appending the directory path in the loop. script not in the same directory as the files. dr1 ="~/test" directory variable

 fileop=open(dr1+"/"+fil,"r")