How to accept command-line args ending in backslash

Question

Here's a barebones Python app that simply prints the command-line arguments passed in:

import sys
if __name__ == "__main__":
    print "Arguments:"
    for i in range(len(sys.argv)):
        print "[%s] = %s" % (i, sys.argv[i])

And here's some sample runs:

python args.py hello world
Arguments:
[0] = args.py
[1] = hello
[2] = world

python args.py "hello world"
Arguments:
[0] = args.py
[1] = hello world

python args.py "hello\world"
Arguments:
[0] = args.py
[1] = hello\world

So far so good. But now when I end any argument with a backslash, Python chokes on it:

python args.py "hello\world\"
Arguments:
[0] = args.py
[1] = hello\world"

python args.py "hello\" world "any cpu"
Arguments:
[0] = args.py
[1] = hello" world any
[2] = cpu

I'm aware of Python's less-than-ideal raw string behavior via the "r" prefix (link), and it seems clear that it's applying the same behavior here.

But in this case, I don't have control of what arguments are passed to me, and I can't enforce that the arguments don't end in a backslash. How can I work around this frustrating limitation?

--

Edit: Thanks to those who pointed out that this behavior isn't specific to Python. It seems to be standard shell behavior (at least on Windows, I don't have a Mac at the moment).

Updated question: How can I accept args ending in a backslash? For example, one of the arguments to my app is a file path. I can't enforce that the client sends it to me without a trailing backslash, or with the backslash escaped. Is this possible in any way?

Answer 1

That's likely the shell treating \ as an escape character, and thus escaping the character. So the shell sends \" as " (because it thinks you are trying to escape the double quote). The solution is to escape the escape character, like so: $ python args.py "hello\world\\".