Python equivalent of unix “strings” utility

Question

I\'m trying to write a script which will extract strings from an executable binary and save them in a file. Having this file be newline-separated isn\'t an option since the

Answer 1

Here's a generator that yields all the strings of printable characters >= min (4 by default) in length that it finds in filename:

import string

def strings(filename, min=4):
    with open(filename, errors="ignore") as f:  # Python 3.x
    # with open(filename, "rb") as f:           # Python 2.x
        result = ""
        for c in f.read():
            if c in string.printable:
                result += c
                continue
            if len(result) >= min:
                yield result
            result = ""
        if len(result) >= min:  # catch result at EOF
            yield result

Which you can iterate over:

for s in strings("something.bin"):
    # do something with s

... or store in a list:

sl = list(strings("something.bin"))

I've tested this very briefly, and it seems to give the same output as the Unix strings command for the arbitrary binary file I chose. However, it's pretty naïve (for a start, it reads the whole file into memory at once, which might be expensive for large files), and is very unlikely to approach the performance of the Unix strings command.