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What's the correct way to handle Unix style wildcard arguments using optparse in Python? I have:

myscript.py:

from optparse import OptionParser
parser = OptionParser()
parser.add_option("--input", dest="input", default=None, nargs=1)
parser.add_option("--outdir", dest="outdir", default=None, nargs=1)
(options, args) = parser.parse_args()

I want to be able to do:

myscript.py --input *.txt --outdir mydir/

I don't want to necessarily read the contents of all the files matching *.txt. I want myscript.py to access their filenames, because some scripts just pass on the filenames to other programs without needing to open/read the files. How can I get an iterator that returns the filenames, while still allowing other arguments like --outdir to be passed after the wildcard friendly option (in this case --input)? thanks.

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    Do you take into account that UNIX shells will expand this glob themselves? Commented Feb 24, 2013 at 0:06
  • @wRAR if they expand it, does it mean that I get passed in a list of filenames? If *.txt was always translated to a.txt,b.txt,... etc there would be no problem. But I don't think that this is what happens Commented Feb 24, 2013 at 0:07
  • Yes, it will be expanded to a space-separated list of filenames. Commented Feb 24, 2013 at 0:21
  • Note: Using optparse is discouraged since python version 2.7. The optparse module is deprecated and will not be developed further; development will continue with the argparse module. See PEP 0389 for more info. Commented Apr 3, 2013 at 23:19

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Unix shells will expand *.txt into separate arguments before they are passed to your program; Windows' command interpreter will not.

Assuming you're using an environment where they aren't expanded first -- that is, invoking python prog.py '*.txt', for instance, you can use glob.glob() to do the expansion yourself.

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It's unusual to require single quotes though.. I want my program to work like other unix utilities. Like wc *.txt. Also parsing it with glob seems complicated - what if I get passed in a filename that has * in it? How can I tell if it's a glob to be expanded or part of the filename?

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