How to replace text using python if a file contains binary code and text both?

Question

I want to replace text of Houdini file(.hip) which contains mixture of Binary code and Text. I have python code which replace text file. When i try to replace Text in Houdini file the file gets Corrupt after replacement.

Can anyone tell me How to replace text in Houdini file without corrupting it?

code:

import fileinput,sys
for line in fileinput.input("file_name",inplace=True):
    line = line.replace("from","to")
    sys.stdout.write(line)

When i try to replace Houdini file(.hip) using this code then file gets corrupt.

Do anyone know how to replace Houdini file without opening it ?

Have you tried opening the file in binary mode? https://docs.python.org/3/library/fileinput.html — Mike Scotty, Jun 15 '18 at 09:37
the file format might encode string lengths… can you tell us /anything/ about the format? i'm inclined to downvote this for "please do magic for me, but i'm going to make you guess!" — , Jun 15 '18 at 09:51
I use 'rb' mode with fileinput but the result was same...Can u tell me other way to do it ? @BoarGules — python_fan, Jun 15 '18 at 11:06
ya I understand that .what i am saying is what is other Library to do it ? Actually i am new in python that is why i have stuck here @BoarGules — python_fan, Jun 15 '18 at 11:10
thanks but this is only for read i want to replace too @BoarGules — python_fan, Jun 15 '18 at 11:14

score 0 · Answer 1 · edited Jun 12 '20 at 05:51

I came across this problem recently and tried the suggestions mentioned in the comments.
Here is the final solution that worked for me:

import re
def UpdateFile(self, file, oldstrg, newStr):
    bytetofind = bytes(oldstrg, encoding='utf-8')
    bytetoreplace = bytes(newStr, encoding='utf-8')
    f = open(file, 'rb+')
    text = f.read()
    text = re.sub(bytetofind , bytetoreplace, text, count=1)
    f.seek(0)
    f.write(text)
    f.close()

The count=1 is there because I wanted to replace only a single instance of that string.
You can change/remove as per your requirements.

How to replace text using python if a file contains binary code and text both?

1 Answers1