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

代码如下:

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