Use python to implement the basic functions of the wc command program.

Use python to implement the basic functions of the wc command program.

The basic python code is used to implement the basic functions of the wc command program in Linux.

 

#! /Usr/bin/env python # encoding: UTF-8 # Author: liwei # Function: wc program by pythonfrom optparse import OptionParserimport sys, osdef opt (): parser = OptionParser () parser. add_option ('-C',' -- char ', dest = 'chars', action = 'store _ true', default = False, help = 'only count chars') parser. add_option ('-W',' -- word', dest = 'word', action = 'store _ true', default = False, help = 'only count word') parser. add_option ('-l',' -- line', dest = 'lines', action = 'store _ true', default = False, help = 'only count lines') parser. add_option ('-n',' -- nototal', dest = 'nototal', action = 'store _ true', default = False, help = 'Don \'t print total information') options, args = parser. parse_args () return options, args # print optionsdef get_count (data): chars = len (data) words = len (data. split () lines = data. count ('\ n') return lines, words, chars # if not options. chars and not options. words and not optionsdef print_wc (options, lines, words, chars, fn): if options. lines: print lines, if options. words: print words, if options. chars: print chars, print fndef main (): options, args = opt () if not (options. lines or options. words or options. chars): options. lines, options. words, options. chars = True, True, True if args: total_lines, total_words, total_chars = 0, 0, 0 for fn in args: if OS. path. isfile (fn): with open (fn) as fd: data = fd. read () lines, words, chars = get_count (data) print_wc (options, lines, words, chars, fn) total_lines + = lines total_words + = words total_chars + = chars elif OS. path. isdir (fn): print> sys. stderr, '% s is a directory' % fn else: sys. stderr. write ('% s: No such file or directory \ n' % fn) # calculate the total field if len (args)> 1 and not options when there are only multiple files. nototal: print_wc (options, total_lines, total_words, total_chars, 'Total') else: fn = 'data = sys. stdin. read () lines, words, chars = get_count (data) print_wc (options, lines, words, chars, fn) if _ name _ = '_ main _': main ()