在python的sys.argv中加注星号

Question

I am attempting to write a script that utilises sys.argv to wrap the scp command. The idea, is that you will be able to run: pyscp folder/* host but if I run this script with those arguments:

import sys

for arg in sys.argv:
    print arg

I get a list of all the folders inside folder :

pyscp.py
folder/0
folder/1
folder/2
folder/3
folder/4
folder/5
folder/67
folder/8
folder/9
host

Answer 1

Assuming a UNIXoid operating system: The shell is expanding the * into the matching files. Try to call your script like

pyscp "folder/*" host

The quotes keep the shell from interpreting the * character.

Answer 2

If you do not escape the asterisk, the shell is performing filename expansion for you. The pattern including the asterisk becomes replaced with an alphabetically sorted list of file names matching the pattern before your Python program becomes executed. You can prevent the shell from performing filename expansion using eg single quotes, ie

pyscp 'folder/*' hostname

You can then do this yourself within Python using the glob module and control things the way you want it.

Answer 3

The shell is expanding the file list for you. You can leverage this by allowing multiple parameters in the command.

import sys
files = sys.argv[1:-1]
host = sys.argv[-1]

Now you have a more flexible program that lets caller jump through whatever hoops he wants for the transfer, like maybe all text files in folder1 plus anything that's changed in the last day in folder2 (on a linux machine):

pyscp folder1/*.txt `find -mtime -1` example.com