以下是mimetypes的版本：#!/usr/bin/env python

"""It is a `filename -> filename.ext` filter.

`ext` is mime-based.

"""

import fileinput

import mimetypes

import os

import sys

from subprocess import Popen, PIPE

if len(sys.argv) > 1 and sys.argv[1] == '--rename':

do_rename = True

del sys.argv[1]

else:

do_rename = False

for filename in (line.rstrip() for line in fileinput.input()):

output, _ = Popen(['file', '-bi', filename], stdout=PIPE).communicate()

mime = output.split(';', 1)[0].lower().strip()

ext = mimetypes.guess_extension(mime, strict=False)

if ext is None:

ext = os.path.extsep + 'undefined'

filename_ext = filename + ext

print filename_ext

if do_rename:

os.rename(filename, filename_ext)

示例：$ ls *.file? | python add-ext.py --rename

avi.file.avi

djvu.file.undefined

doc.file.dot

gif.file.gif

html.file.html

ico.file.obj

jpg.file.jpe

m3u.file.ksh

mp3.file.mp3

mpg.file.m1v

pdf.file.pdf

pdf.file2.pdf

pdf.file3.pdf

png.file.png

tar.bz2.file.undefined

遵循@Phil H的响应，遵循@csl的响应：#!/usr/bin/env python

"""It is a `filename -> filename.ext` filter.

`ext` is mime-based.

"""

# Mapping of mime-types to extensions is taken form here:

# http://as3corelib.googlecode.com/svn/trunk/src/com/adobe/net/MimeTypeMap.as

mime2exts_list = [

["application/andrew-inset","ez"],

["application/atom+xml","atom"],

["application/mac-binhex40","hqx"],

["application/mac-compactpro","cpt"],

["application/mathml+xml","mathml"],

["application/msword","doc"],

["application/octet-stream","bin","dms","lha","lzh","exe","class","so","dll","dmg"],

["application/oda","oda"],

["application/ogg","ogg"],

["application/pdf","pdf"],

["application/postscript","ai","eps","ps"],

["application/rdf+xml","rdf"],

["application/smil","smi","smil"],

["application/srgs","gram"],

["application/srgs+xml","grxml"],

["application/vnd.adobe.apollo-application-installer-package+zip","air"],

["application/vnd.mif","mif"],

["application/vnd.mozilla.xul+xml","xul"],

["application/vnd.ms-excel","xls"],

["application/vnd.ms-powerpoint","ppt"],

["application/vnd.rn-realmedia","rm"],

["application/vnd.wap.wbxml","wbxml"],

["application/vnd.wap.wmlc","wmlc"],

["application/vnd.wap.wmlscriptc","wmlsc"],

["application/voicexml+xml","vxml"],

["application/x-bcpio","bcpio"],

["application/x-cdlink","vcd"],

["application/x-chess-pgn","pgn"],

["application/x-cpio","cpio"],

["application/x-csh","csh"],

["application/x-director","dcr","dir","dxr"],

["application/x-dvi","dvi"],

["application/x-futuresplash","spl"],

["application/x-gtar","gtar"],

["application/x-hdf","hdf"],

["application/x-javascript","js"],

["application/x-koan","skp","skd","skt","skm"],

["application/x-latex","latex"],

["application/x-netcdf","nc","cdf"],

["application/x-sh","sh"],

["application/x-shar","shar"],

["application/x-shockwave-flash","swf"],

["application/x-stuffit","sit"],

["application/x-sv4cpio","sv4cpio"],

["application/x-sv4crc","sv4crc"],

["application/x-tar","tar"],

["application/x-tcl","tcl"],

["application/x-tex","tex"],

["application/x-texinfo","texinfo","texi"],

["application/x-troff","t","tr","roff"],

["application/x-troff-man","man"],

["application/x-troff-me","me"],

["application/x-troff-ms","ms"],

["application/x-ustar","ustar"],

["application/x-wais-source","src"],

["application/xhtml+xml","xhtml","xht"],

["application/xml","xml","xsl"],

["application/xml-dtd","dtd"],

["application/xslt+xml","xslt"],

["application/zip","zip"],

["audio/basic","au","snd"],

["audio/midi","mid","midi","kar"],

["audio/mpeg","mp3","mpga","mp2"],

["audio/x-aiff","aif","aiff","aifc"],

["audio/x-mpegurl","m3u"],

["audio/x-pn-realaudio","ram","ra"],

["audio/x-wav","wav"],

["chemical/x-pdb","pdb"],

["chemical/x-xyz","xyz"],

["image/bmp","bmp"],

["image/cgm","cgm"],

["image/gif","gif"],

["image/ief","ief"],

["image/jpeg","jpg","jpeg","jpe"],

["image/png","png"],

["image/svg+xml","svg"],

["image/tiff","tiff","tif"],

["image/vnd.djvu","djvu","djv"],

["image/vnd.wap.wbmp","wbmp"],

["image/x-cmu-raster","ras"],

["image/x-icon","ico"],

["image/x-portable-anymap","pnm"],

["image/x-portable-bitmap","pbm"],

["image/x-portable-graymap","pgm"],

["image/x-portable-pixmap","ppm"],

["image/x-rgb","rgb"],

["image/x-xbitmap","xbm"],

["image/x-xpixmap","xpm"],

["image/x-xwindowdump","xwd"],

["model/iges","igs","iges"],

["model/mesh","msh","mesh","silo"],

["model/vrml","wrl","vrml"],

["text/calendar","ics","ifb"],

["text/css","css"],

["text/html","html","htm"],

["text/plain","txt","asc"],

["text/richtext","rtx"],

["text/rtf","rtf"],

["text/sgml","sgml","sgm"],

["text/tab-separated-values","tsv"],

["text/vnd.wap.wml","wml"],

["text/vnd.wap.wmlscript","wmls"],

["text/x-setext","etx"],

["video/mpeg","mpg","mpeg","mpe"],

["video/quicktime","mov","qt"],

["video/vnd.mpegurl","m4u","mxu"],

["video/x-flv","flv"],

["video/x-msvideo","avi"],

["video/x-sgi-movie","movie"],

["x-conference/x-cooltalk","ice"]]

#NOTE: take only the first extension

mime2ext = dict(x[:2] for x in mime2exts_list)

if __name__ == '__main__':

import fileinput, os.path

from subprocess import Popen, PIPE

for filename in (line.rstrip() for line in fileinput.input()):

output, _ = Popen(['file', '-bi', filename], stdout=PIPE).communicate()

mime = output.split(';', 1)[0].lower().strip()

print filename + os.path.extsep + mime2ext.get(mime, 'undefined')

以下是旧python版本(未测试)的代码片段：#NOTE: take only the first extension

mime2ext = {}

for x in mime2exts_list:

mime2ext[x[0]] = x[1]

if __name__ == '__main__':

import os

import sys

# this version supports only stdin (part of fileinput.input() functionality)

lines = sys.stdin.read().split('\n')

for line in lines:

filename = line.rstrip()

output = os.popen('file -bi ' + filename).read()

mime = output.split(';')[0].lower().strip()

try: ext = mime2ext[mime]

except KeyError:

ext = 'undefined'

print filename + '.' + ext

它应该可以在Python2.3.5上工作(我想)。