用Python实现换行符转换的脚本的教程

很简单的一个东西，在'\n'、'\r\n'、'\r'3中换行符之间进行转换。
用法

usage: eol_convert.py [-h] [-r] [-m {u,p,w,m,d}] [-k] [-f]
                      filename [filename ...]

Convert Line Ending

positional arguments:
  filename        file names

optional arguments:
  -h, --help      show this help message and exit
  -r              walk through directory
  -m {u,p,w,m,d}  mode of the line ending
  -k              keep output file date
  -f              force conversion of binary files

源码

这只能算是argparse模块和os模块的utime()、stat()、walk()的一个简单的练习。可以用，但还相当不完善。

#!/usr/bin/env python
 #2009-2011 dbzhang800
 import os
 import re
 import os.path

def convert_line_endings(temp, mode):
   if mode in ['u', 'p']: #unix, posix
     temp = temp.replace('\r\n', '\n')
     temp = temp.replace('\r', '\n')
   elif mode == 'm':   #mac (before Mac OS 9)
     temp = temp.replace('\r\n', '\r')
     temp = temp.replace('\n', '\r')
   elif mode == 'w':   #windows
     temp = re.sub("\r(?!\n)|(?<!\r)\n", "\r\n", temp)
   return temp

def convert_file(filename, args):
   statinfo = None
   with file(filename, 'rb+') as f:
     data = f.read()
     if '\0' in data and not args.force: #skip binary file... ?
       print '％s is a binary file?, skip...' ％ filename
       return
     newdata = convert_line_endings(data, args.mode)
     if (data != newdata):
       statinfo = os.stat(filename) if args.keepdate else None
       f.seek(0)
       f.write(newdata)
       f.truncate()
   if statinfo:
     os.utime(filename, (statinfo.st_atime, statinfo.st_mtime))
   print filename

def walk_dir(d, args):
   for root, dirs, files in os.walk(d):
     for name in files:
       convert_file(os.path.join(root, name), args)

if __name__ == '__main__':
   import argparse
   import sys
   parser = argparse.ArgumentParser(description='Convert Line Ending')
   parser.add_argument('filename', nargs='+', help='file names')
   parser.add_argument('-r', dest='recursive', action='store_true',
       help='walk through directory')
   parser.add_argument('-m', dest='mode', default='d', choices='upwmd',
       help='mode of the line ending')
   parser.add_argument('-k', dest='keepdate', action='store_true',
       help='keep output file date')
   parser.add_argument('-f', dest='force', action='store_true',
       help='force conversion of binary files')
   args = parser.parse_args()
   if args.mode == 'd':
     args.mode = 'w' if sys.platform == 'win32' else 'p'

for filename in args.filename:
     if os.path.isdir(filename):
       if args.recursive:
         walk_dir(filename, args)
       else:
         print '％s is a directory, skip...' ％ filename
     elif os.path.exists(filename):
       convert_file(filename, args)
     else:
       print '％s does not exist' ％ filename