Python: Detect all strings in binary file?

if you don't care about the content of the output, it's very easy to achieve if you simple ignore all decoding error:

in python2:

with open('file') as fd:
    print fd.read().decode('ascii', errors='ignore')

in python3:

import codecs
with open('file') as fd:
    print(codecs.decode(fd.read(), 'ascii', errors='ignore'))

in any ways, errors='ignore' just ignore all errors during decoding.

further reference: https://docs.python.org/2/library/codecs.html

python3: https://docs.python.org/3.5/library/codecs.html

The following would print a list of all words of length 4 or more:

import re

with open(r"my_binary_file", "rb") as f_binary:
    print re.findall("([a-zA-Z]{4,})", f_binary.read())

By doing this, it cuts down on some non-text matches but might of course miss something you were looking for. strings also has a default value of 4.

Check byte by byte to see if it falls between 0x20 and 0x7F. That should print out if the byte is a readable ASCII character.

The following should find all strings of length 4 and more (which is what strings does by default) in the bytes array:

def strings(data):
    cleansed = "".join(map(lambda byte: byte if byte >= chr(0x20) and byte <= chr(0x7F) else chr(0), data))
    return filter(lambda string: len(string) >= 4, cleansed.split(chr(0)))