Python: Simulate the linux Command cat

Python: Simulate the linux Command cat

Simulate the cat command in linux and print the file name entered from the command line.

 

#! /Usr/bin/python # Filename: cat. pyhelpString = ''' \ This program prints files to the standard output. any number of files can be specified. options include: -- version: Prints the version number -- help: Display this help ''' import sysdef readfile (filename): ''' Print a file to the standard output. '''f = file (filename) while True: line = f. readline () if len (line) = 0: break print line, f. close () # Script start from hereif len (sys. argv) <2: print 'no action specified. 'sys. exit () if sys. argv [1]. startswith ('--'): option = sys. argv [1] [2:] if option = 'version' or option = 'V ': print 'version 1.2 'elif option = 'help' or option = 'H': print helpString else: print 'unknown option. 'sys. exit () else: for filename in sys. argv [1:]: readfile (filename) print 'done'