How to edit a file in python without a temporary sacrificial file?

Asked Nov 01 '17 at 11:28

Active Nov 01 '17 at 11:32

Viewed 68 times

I have a script that opens a csv file, applies a substitution and then writes out to a new file then deletes the old one.

with open('file-presub.csv', 'r') as reader, open('file-postsub.csv','w') as writer:
    for row in reader:
        row = re.sub('(\+*,[^,]*,[^,]*,[^,]*,\ 0)', ' (Core)\\g<1>', row)
        writer.write(row)

os.remove("file-presub.csv")

Is there any way I can make it so I just edit the file-presub.csv and write it out with the same filename instead of making a second file and deleting the original? I'd like to avoid importing OS just for this one line.

Of course if it's not possible I'm able to import OS, just asking if it's possible at all.

edited Nov 01 '17 at 11:32

FunkySayu

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asked Nov 01 '17 at 11:28

BaconCatBug

1

You can open file both in read and write modes: https://stackoverflow.com/questions/6648493/open-file-for-both-reading-and-writing – Tsagana Nokhaeva Nov 01 '17 at 11:34
1

instead of opening first file in read mode you can open it in write mode and perform write operations without having another file. – Mahesh Karia Nov 01 '17 at 11:35
Look at the `fileinput` module. – cs95 Nov 01 '17 at 11:35

How to edit a file in python without a temporary sacrificial file?

0 Answers0