ptyhon command line parms

parms.py

#!/usr/bin/python

import sys, getopt

print 'Number of arguments:', len(sys.argv), 'arguments.'
print 'Argument List:', str(sys.argv)


def usage(msg=None):
   if msg:
      print msg
   print '%s -i <inputfile> -o <outputfile>' % sys.argv[0]
   sys.exit(1)

def main(argv):

   # parms needed to be filled through cli options
   inputfile = None
   outputfile = None

   # parse cli options
   try:
      opts, args = getopt.getopt(argv,"hi:o:",["ifile=","ofile="])
   except getopt.GetoptError as e:
      usage(str(e))

   # split the cli options into vars
   # and / or take action
   for opt, arg in opts:
      if opt == '-h':
         usage('help about parameters:')
      elif opt in ("-i", "--ifile"):
         inputfile = arg
      elif opt in ("-o", "--ofile"):
         outputfile = arg
   print 'Input file is ', inputfile
   print 'Output file is ', outputfile

   # check required parms
   if inputfile == None or outputfile == None:
      usage('Needed input parms not given:')

   # if we are here the parms are filled
   # do program logic from here on

if __name__ == "__main__":
   main(sys.argv[1:])