How to use getopt/OPTARG in Python? How to shift arguments if too many arguments (9) are given? How to use getopt/OPTARG in Python? How to shift arguments if too many arguments (9) are given? python python

How to use getopt/OPTARG in Python? How to shift arguments if too many arguments (9) are given?


This is an example of how I do it, I usually use the same basic template:

import sysimport getopttry:    opts, args = getopt.getopt(sys.argv[1:], 'm:p:h', ['miner=', 'params=', 'help'])except getopt.GetoptError:    usage()    sys.exit(2)for opt, arg in opts:    if opt in ('-h', '--help'):        usage()        sys.exit(2)    elif opt in ('-m', '--miner'):        miner_name = arg    elif opt in ('-p', '--params'):        params = arg    else:        usage()        sys.exit(2)

I don't think there is any 9 parameter limit.


A google search would have helped. Have a look at the getopt and argparse modules in the standard library:

import argparseparser = argparse.ArgumentParser(description='Process some integers.')parser.add_argument('integers', metavar='N', type=int, nargs='+',                   help='an integer for the accumulator')parser.add_argument('--sum', dest='accumulate', action='store_const',                   const=sum, default=max,                   help='sum the integers (default: find the max)')args = parser.parse_args()print args.accumulate(args.integers)

Then run it as expected:

$ prog.py -husage: prog.py [-h] [--sum] N [N ...]Process some integers.positional arguments: N           an integer for the accumulatoroptional arguments: -h, --help  show this help message and exit --sum       sum the integers (default: find the max)

When run with the appropriate arguments, it prints either the sum or the max of the command-line integers:

$ prog.py 1 2 3 44$ prog.py 1 2 3 4 --sum10

This is straight from the standard library.


Have you tried reading the python docs for the module getopt (http://docs.python.org/library/getopt.html?highlight=getopt#module-getopt)? It provides a simple example of how the getopt is used. What do you mean by shift arguments? If you want to check that the user does not use more than 9 arguments, you can check the length of the sys.argv list, which contains all the options/arguments passed to the script. The first element is the name of the script which is invoked, so the length is always at least 1. You could do something like:

if len(sys.argv) > 10    print('Too many arguments.')