共计 1789 个字符，预计需要花费 5 分钟才能阅读完成。
今天在看一个代码的时候发现glob，源代码是需要将子目录里面所有带指定后缀名的文件检索出来，我们并不关心文件的名字，只关心文件后缀名。代码中给出了glob函数的操作，通过给出正则表达式匹配所有的文件并返回列表，找到则不为空。有了这个就不需要自己去便利每一个子目录了。。。。Python的包真的是多，知道能省很多时间，不知道又要自己造轮子了。。。。。
glob 路径模式匹配
The glob module finds all the pathnames matching a specified pattern according to the rules used by the Unix shell, although results are returned in arbitrary order. No tilde expansion is done, but *, ?, and character ranges expressed with [] will be correctly matched. This is done by using the os.listdir() and fnmatch.fnmatch() functions in concert, and not by actually invoking a subshell. Note that unlike fnmatch.fnmatch(),glob treats filenames beginning with a dot (.) as special cases. (For tilde and shell variable expansion, use os.path.expanduser() and os.path.expandvars().)
For a literal match, wrap the meta-characters in brackets. For example, '[?]' matches the character '?'.
glob.glob(pathname)- Return a possibly-empty list of path names that match pathname, which must be a string containing a path specification. pathname can be either absolute (like
/usr/src/Python-1.5/Makefile) or relative (like../../Tools/*/*.gif), and can contain shell-style wildcards. Broken symlinks are included in the results (as in the shell).
glob.iglob(pathname)- Return an iterator which yields the same values as
glob()without actually storing them all simultaneously.New in version 2.5.
For example, consider a directory containing only the following files: 1.gif, 2.txt, and card.gif. glob() will produce the following results. Notice how any leading components of the path are preserved.
>>> import glob
>>> glob.glob('./[0-9].*')
['./1.gif', './2.txt']
>>> glob.glob('*.gif')
['1.gif', 'card.gif']
>>> glob.glob('?.gif')
['1.gif']If the directory contains files starting with . they won’t be matched by default. For example, consider a directory containing card.gif and .card.gif:
在这里要注意一下开头是 . 的文件，这个是不能被正则式 * 识别出来，这一点需要注意一下
>>> import glob
>>> glob.glob('*.gif')
['card.gif']
>>> glob.glob('.c*')
['.card.gif']
